Outcomes and bleb-related complications of trabeculectomy

Long-Term Efficacy of Successful Excisional Goniotomy with the Kahook Dual Blade

Purpose

To report clinical outcomes of successful excisional goniotomy with the Kahook Dual Blade (KDB), through 60 months.

Patients and methods

This was a noncomparative, single-surgeon, retrospective review of eyes receiving successful KDB goniotomy with or without concomitant phacoemulsification between October 2015 and January 2016 with five years of uninterrupted follow-up. Intraocular pressure (IOP), number of glaucoma medications, best corrected visual acuity (BCVA), and complications were recorded. Primary outcomes included changes from baseline in IOP, medication use, and BCVA, through five years.

Results

Fifty-two eyes of 28 patients were analyzed. Most eyes had mild primary open angle glaucoma (73%). Of the eyes analyzed, 41 underwent combined surgery and 11 underwent standalone surgery. With all eyes combined, mean (standard deviation) baseline IOP was 21.0 (4.1) mmHg and mean baseline medication use was 1.8 (1.1) medications per eye. Across time points at months 6, 12, 24, 36, 48, and 60, mean postoperative IOP ranged from 13.0 to 13.7 mmHg, representing mean reductions of 7.3-8.0 mmHg (34.7-38.3%; p <0.0001 at every time point). Similarly, mean medication use ranged from 0.4 to 0.6 medications per eye, representing mean reductions of 1.2-1.4 medications (66-75.5%; p <0.0001 at every time point). Mean logMAR BCVA improved from 0.321 (0.177) preoperatively to 0.015 (0.035) at month 60 (p < 0.0001).

Conclusion

In eyes not requiring secondary surgical procedures (eg, long-term surgical successes), excisional goniotomy provided clinically and statistically significant reductions in both IOP and the need for medications that were highly consistent through five years of follow-up. KDB goniotomy appears to be highly successful in Caucasian patients with open angle glaucoma on ≥1 IOP-lowering medications at baseline and with no history of prior ocular surgery. Successful excisional goniotomy with the KDB can be expected to improve long-term glaucoma-related visual outcomes through IOP reduction and to improve quality of life through medication reduction.

Two-year outcomes of anterior versus posterior scleral application of mitomycin C-soaked sponge in trabeculectomy

PURPOSE

To compare the safety and efficacy of two different application methods of mitomycin C (MMC)-soaked sponge in trabeculectomy.

STUDY DESIGN

Retrospective study.

METHODS

We included 71 eyes of 71 patients that had undergone trabeculectomy. In the anterior scleral application group, 36 eyes were treated using the long side of the MMC-soaked sponge placed parallel to the limbus. The efficacy and safety in these eyes were compared with eyes treated with the posterior scleral application group, consisting of 35 eyes treated with the long side of the MMC-soaked sponge placed perpendicular to the limbus. The follow-up period was 2 years. The safety of the procedure, including bleb morphology and complications, was the primary outcome, while the success rate was the secondary outcome.

RESULTS

The cumulative success rate at 2 years postoperatively was 94.4% in the anterior and and 94.3% in the posterior scleral application group (P = 1.000). However, with the posterior scleral application of the MMC-soaked sponge, blebs were more low-lying (P = 0.048), less in extent (P < 0.001), more normally vascularized (P = 0.027) and more posteriorly directed (P < 0.001). Furthermore, the incidence of thin-walled cystic bleb (P = 0.028) and bleb leakage (P = 0.025) was significantly lower in the posterior scleral application group than in the anterior group.

CONCLUSION

Although there were similar success rates, the posterior scleral application of MMC-soaked sponge with trabeculectomy was safer with a better bleb morphology than the anterior scleral application.

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.

Therapeutic strategies for glaucoma and optic neuropathies

Glaucoma is a neurodegenerative eye disease that causes permanent vision impairment. The main pathological characteristics of glaucoma are retinal ganglion cell (RGC) loss and optic nerve degeneration. Glaucoma can be caused by elevated intraocular pressure (IOP), although some cases are congenital or occur in patients with normal IOP. Current glaucoma treatments rely on medicine and surgery to lower IOP, which only delays disease progression. First-line glaucoma medicines are supported by pharmacotherapy advancements such as Rho kinase inhibitors and innovative drug delivery systems. Glaucoma surgery has shifted to safer minimally invasive (or microinvasive) glaucoma surgery, but further trials are needed to validate long-term efficacy. Further, growing evidence shows that adeno-associated virus gene transduction and stem cell-based RGC replacement therapy hold potential to treat optic nerve fiber degeneration and glaucoma. However, better understanding of the regulatory mechanisms of RGC development is needed to provide insight into RGC differentiation from stem cells and help choose target genes for viral therapy. In this review, we overview current progress in RGC development research, optic nerve fiber regeneration, and human stem cell-derived RGC differentiation and transplantation. We also provide an outlook on perspectives and challenges in the field.

Safety and Efficacy of Goniotomy following Failed Surgery for Glaucoma

PRCIS

Goniotomy (GT) is an alternative surgery for patients with prior failed surgery for glaucoma.

PURPOSE

To evaluate the efficacy and safety of GT in patients with prior failed surgery for glaucoma.

MATERIALS AND METHODS

A prospective, observational multicentered study was performed for patients who underwent GT with prior single or multiple surgery for glaucoma. Outcome measures included intraocular pressure (IOP) change, best-corrected visual acuity change, ocular hypotensive medication use, and occurrence of adverse events through 12 months. Complete success was defined as a postoperative IOP within 6-18 mmHg and a 20% reduction from baseline without ocular hypotensive medications. Qualified success was the same as the definition of complete success, except for postoperative use of medication. Logistic regression models were used to investigate the potential factors for surgical success.

RESULTS

A total of 38 eyes of 34 patients were included. Twenty-three eyes had only 1 prior surgery, 13 eyes had 2 prior surgeries, 1 eye had 3 prior surgeries, and 1 eye had 4 prior surgeries. At month 12, there was complete success in 42.1% of the eyes and qualified success in 78.9% of the eyes. Preoperatively, the mean IOP was 29.4±6.9 mmHg and the median number of glaucoma medications used was 3.0 (2.0, 4.0); this decreased to 16.7±3.6 mmHg (43.2% reduction; P <0.001) and 2.0 (0.0, 3.0) ( P <0.001) at month 12, respectively. The most common complications included hyphema (13.2%), IOP spike (7.9%), and corneal edema (5.2%). Older age significantly contributed to surgical success.

CONCLUSIONS

GT seems to be a safe and effective procedure for patients with prior failed surgery for glaucoma.

Long-Term Surgical Outcomes and Possible Postoperative Complication with Severe Corneal Endothelial Cell Loss After Trabeculectomy for Cytomegalovirus-Associated Anterior Uveitis with Secondary Glaucoma

PURPOSE

We assess long-term surgical outcomes after an initial trabeculectomy for cytomegalovirus-associated anterior uveitis with secondary glaucoma (CMV-SG).

METHODS

We retrospectively reviewed the medical records of 16 eyes of 15 patients with CMV-SG and 157 eyes of 157 patients with primary open-angle glaucoma. The average follow-up period was approximately 3 years. Surgical success was defined as intraocular pressure (IOP) below 18 mmHg and at least 20% lower than baseline.

RESULTS

Kaplan-Meier survival analysis revealed that bleb survival rates were not significantly different in the CMV-SG and POAG groups (P = 0.75). Bullous keratopathy occurred in 2 of 16 eyes with CMV-SG postoperatively but did not occur in the POAG group. The corneal endothelial cell density decreased by 34.2 ± 22.7% in the CMV-SG group during an average follow-up period of 2.7 ± 2.0 years.

CONCLUSION

Trabeculectomy effectively controlled IOP in CMV-SG, but attention must be paid to corneal endothelial cell loss.

Noncontact Conjunctiva: A Better Mitomycin C Application Site for Trabeculectomy

INTRODUCTION

Bleb scarring is the most important complication of trabeculectomy. Changing the application position of mitomycin C (MMC) during trabeculectomy might affect the surgery outcome. Our aim is to compare the effectiveness and safety of intraocular pressure (IOP) lowering in two different application sites of mitomycin in trabeculectomy.

METHODS

This retrospective trial compared the surgical outcomes of 177 eyes that underwent trabeculectomy with adjunctive mitomycin C. In 70 eyes, an MMC-soaked sponge was applied under the scleral flap without touching Tenon's capsule. In 107 eyes, an MMC-soaked sponge was applied under the scleral flap covered by Tenon's capsule. Outcome measures were the IOP, best-corrected visual acuity (BCVA), success rates, and incidence of complications.

RESULTS

Within both groups, a highly significant IOP reduction was seen during follow-up. The effectiveness in reducing IOP and the change in best-corrected visual acuity (BCVA) were similar between the two groups. Thin-walled blebs and postoperative hypotony were seen more often when MMC-soaked sponges were applied under the scleral flap covered by Tenon's capsule (P = 0.008 and P = 0.012, respectively). There was no significant difference in BCVA or other complications in either group.

CONCLUSION

Since the effectiveness of IOP reduction was similar between both groups and with a low incidence of thin-walled blebs and hypotony, the subscleral application without touching Tenon's capsule seems to be the safer application site of MMC during trabeculectomy.

Clinicopathological features of corneal invasion by filtering bleb

PURPOSE

To describe the clinicopathological characteristics and explore the possible etiology of cornea invasion by filtering bleb (CIFB) after filtering surgery.

METHODS

We reviewed 22 patients treated for CIFB between March 2005 and March 2022. The patients were followed up for more than 1 year. Slit-lamp examination, optical coherence tomography (OCT), ultrasound biomicroscopy, and histopathological examination were performed to observe the morphology of the bleb and depth of corneal invasion. Depending on the severity of the lesion, treatments consisting of local massage, acupuncture separation, or surgical resection were administered.

RESULTS

The mean age of the patients was 56.3 ± 8.8 years. All patients underwent filtering surgery in the moderate or advanced stage of glaucoma. The filtering bleb was closely connected with the cornea, and its posterior boundary was locally adhered. Forward displacement of the internal opening of the filtering bleb was found in 4 of 7 surgically treated patients. OCT and pathological examination showed that the filtering blebs invaded the corneal stroma. Removal of the adhesion of the posterior boundary of the filtering bleb by different treatment methods successfully improved the patients' conditions.

CONCLUSION

Filtering blebs can invade the corneal stroma. Adhesion of the posterior boundary and forward displacement of the internal opening of the filtering bleb are the possible causes of CIFB. Removal of the adhesion of the posterior boundary of the filtering bleb can halt the progression of CIFB.

Survival of Visual Function in Patients with Advanced Glaucoma after Standard Guarded Trabeculectomy with MMC

Surgical intervention in patients with severe glaucoma remains controversial, especially in unilateral cases with a minimally affected fellow eye. Many question the benefit of trabeculectomy in such cases due to high complication rates and prolonged recovery. In this retrospective, non-comparative, interventional case series we aimed to determine the effect of trabeculectomy or combined phaco-trabeculectomy on the visual function of advanced glaucoma patients. Consecutive cases with perimetric mean deviation loss worse than -20 dB were included. Survival of visual function according to five predetermined visual acuity and perimetric criteria was set as the primary outcome. Qualified surgical success utilizing two different sets of criteria commonly used in the literature constituted secondary outcomes. Forty eyes with average baseline visual field mean deviation -26.3 ± 4.1 dB were identified. The average pre-operative intraocular pressure was 26.5 ± 11.4 mmHg and decreased to 11.4 ± 4.0 mmHg (p < 0.001) after an average follow-up of 23.3 ± 15.5 months. Visual function was preserved at two years in 77% or 66% of eyes respectively according to two different sets of visual acuity and perimetric criteria. Qualified surgical success was 89%, 72% at 1 and 3 years respectively. Trabeculectomy and/or phaco-trabeculectomy is associated with meaningful visual outcomes in patients with uncontrolled advanced glaucoma.

Trabeculectomy Tenon Advancement Technique May Reduce Bleb-Related Infections

PRCIS

Trabeculectomy using the Tenon advancement technique with a fornix-based (FB) conjunctival flap showed avascular bleb formation less frequently and had a significantly lower risk of developing bleb-related infections than trabeculectomy with a limbus-based conjunctival flap.

PURPOSE

To determine whether the Tenon advancement technique for trabeculectomy with a FB conjunctival flap is effective in preventing bleb-related infections.

MATERIALS AND METHODS

This was a single-center, nonrandomized retrospective cohort study of 998 eyes from 854 patients with glaucoma who underwent trabeculectomy with mitomycin C. Trabeculectomy procedures were categorized into 3 groups: limbus-based (LB, 296 eyes), FB without Tenon advancement (FBTA-, 167 eyes), and FB with Tenon advancement (FBTA+, 535 eyes). The cumulative incidence of bleb-related infections and the rate of surgical success during the 5-year postoperative follow-up period were analyzed using Kaplan-Meier survival analysis and Cox proportional hazards models. Intraocular pressure (IOP) reduction of <20% from baseline or additional glaucoma surgeries was deemed a surgical failure. Surgical success with or without IOP-lowering medications was evaluated according to different IOP criteria.

RESULTS

Ten eyes developed bleb-related infections (8 eyes in the LB group and 1 eye in both the FBTA- and FBTA+ groups each). The cumulative probability of bleb-related infections in the LB, FBTA-, and FBTA+ groups was 4.8±1.7% (± standard error), 0.8±0.8%, and 0.3±0.3%, respectively. The FBTA+ group had a significantly lower risk of bleb-related infections than the LB group (hazard ratio, 0.06; 95% confidence interval, 0.01 to 0.39; P =0.009). The FBTA+ group did not have a higher risk of surgical failure.

CONCLUSION

The Tenon advancement technique for trabeculectomy using an FB conjunctival flap may be effective in preventing bleb-related infections without compromising surgical success.

Racial Disparities Affecting Black Patients in Glaucoma Diagnosis and Management

Black patients are more affected by glaucoma and suffer from more advanced disease. Diagnostic challenges among black patients with glaucoma include lower rates of diagnostic testing and thinner average central corneal thickness, the latter of which affects intraocular pressure measurement. Treatment challenges include poor follow-up, medication adherence, and trust in providers. Black patients undergoing trabeculectomy have higher rates of failure compared to white patients. Race is not a definitive factor affecting success for tube shunts, laser trabeculoplasty, cyclophotocoagulation, and micro-invasive glaucoma surgeries, but the body of evidence is limited by low inclusion of black patients in these studies. Future steps should include increased attention toward improving trust between patients and providers, improving access to care, and increased representation of black patients in glaucoma research to better understand factors affecting racial disparities in glaucoma management and outcomes in this population disproportionately affected by the disease.

Racial Disparities Affecting Black Patients In Glaucoma Diagnosis And Management

Black patients are more affected by glaucoma and suffer from more advanced disease. Diagnostic challenges among black patients with glaucoma include lower rates of diagnostic testing and thinner average central corneal thickness, the latter of which affects intraocular pressure measurement. Treatment challenges include poor follow-up, medication adherence, and trust in providers. Black patients undergoing trabeculectomy have higher rates of failure compared to white patients. Race is not a definitive factor affecting success for tube shunts, laser trabeculoplasty, cyclophotocoagulation, and micro-invasive glaucoma surgeries, but the body of evidence is limited by low inclusion of black patients in these studies. Future steps should include increased attention toward improving trust between patients and providers, improving access to care, and increased representation of black patients in glaucoma research to better understand factors affecting racial disparities in glaucoma management and outcomes in this population disproportionately affected by the disease.

Six year outcomes of combined phacoemulsification surgery and endoscopic cyclophotocoagulation in refractory glaucoma

PURPOSE

This study is to describe the 6-year results of combined phacoemulsification surgery and endoscopic cyclophotocoagulation (Phaco-ECP) surgery in patients with uncontrolled glaucoma and no previous glaucoma surgery.

METHODS

This is a retrospective case series of 84 eyes. The primary outcome measure was intraocular pressure (IOP) reduction 6 years postoperatively. Secondary outcome measures were the cumulative probability of failure of the surgical procedure at 6 years. Failure was defined as IOP higher than 21 mm Hg or lower than 6 mm Hg or IOP not reduced by 20% from baseline at the 1, 2, 3, 4, 5, or 6-year time points or further laser or other surgery to reduce IOP at any timepoint.

RESULTS

There was a statistically significant decrease in mean IOP from 18.9 mmHg pre-operatively to 13.7, 12.8, 13.0, 12.7, 12.5, and 12.3 mmHg at the 1, 2, 3, 4, 5, and 6 years post-operatively respectively (p < 0.001). Fifty-seven (68%) reached criteria for failure by 6 years. In 36% of cases, this was due to inadequate IOP control, whereas 32% required further laser or surgery. When we excluded patients who only had selective laser trabeculoplasty rather than further surgery, the failure rate reduced to 51%. Eleven percent had a post-operative complication, 2.4% requiring further surgical intervention.

CONCLUSIONS

At 6 years postoperatively, combined phaco-ECP achieved a significant reduction in IOP in patients with uncontrolled glaucoma and no previous drainage surgery. Significant complications were uncommon, but 68% was classified as surgical failures by the six year point.

Minimally Invasive Glaucoma Surgery: Safety of Individual Devices

Primary open-angle glaucoma progression in those already on maximal medical therapy has traditionally been treated with trabeculectomy, a surgical procedure that carries a high degree of morbidity. In the last few decades, significant advances have been made in the field of minimally invasive glaucoma surgery (MIGS) devices, which aim to defer or prevent trabeculectomy via less arduous surgical techniques in certain types of glaucoma. Although reviews have been published examining the efficacy of various MIGS techniques, no article synthesises the comparative safety of all available devices. We performed a literature review examining the safety of MIGS devices. Fifteen devices were included, variously attempting to increase aqueous outflow through the trabecular meshwork or the suprachoroidal space, shunting into the subconjunctival space, or reducing aqueous production through ciliary body ablation. Notably, the earliest product attempting to increase outflow to the suprachoroidal space, Alcon's CyPass Micro-Stent, was withdrawn from the market due to concerns regarding increased corneal endothelial cell loss at five years post-implantation. All other devices were described as well-tolerated, with the most common adverse effects including hyphaema, intraocular pressure spikes, and device migration or obstruction. MIGS devices are purported to be uniformly safe, and many studies report no statistically significant increased complications beyond those associated with cataract surgery alone. It is important to note, however, the generally poor quality of current studies, with a dearth of randomised, or even prospective, data, and a large proportion of studies funded by device producers.

Comparison of surgical outcomes with and without Ologen collagen matrix augmentation during XEN gel stent implantation

Background

To compare the surgical outcomes and postoperative complications with and without Ologen collagen matrix augmentation during XEN gel stent implantation.

Methods

We retrospectively analyzed patients who underwent XEN gel stent implantation with an ab externo technique. The amount of intraocular pressure (IOP) reduction, percentage of postoperative complications and additional management, and surgical success defined as IOP reduction greater than 20% compared with the preoperative IOP measurement were compared between Ologen-augmented and non-augmented groups. Groups of patients who underwent XEN gel stent implantation alone and combined with phacoemulsification were analyzed separately.

Results

A total 103 eyes of 103 participants were included. Of those, 72 eyes underwent standalone XEN gel stent implantation: 42 eyes with Ologen augmentation (Oloxen group) and 30 eyes without Ologen augmentation (Xen group). Thirty-one eyes underwent XEN gel stent implantation with phacoemulsification: 19 eyes with Ologen augmentation (Phaco-Oloxen group) and 12 eyes without Ologen augmentation (PhacoXen group). The surgical success rate at six months postoperatively was not different between the Oloxen and Xen groups (56.4% vs 43.3%, P > 0.05) or between the Phaco-Oloxen group and PhacoXen group (57.9% vs 41.7%, P > 0.05). The prevalence of postoperative hypotony, 5-fluorouracil injections, use of anti-glaucoma medications, bleb needling, and additional glaucoma surgeries was not different between the Oloxen and Xen groups or between the Phaco-Oloxen and PhacoXen groups when assessed six months postoperatively.

Conclusions

All groups showed significant IOP reduction after XEN gel stent implantation, but there was no significant difference between the Ologen collagen matrix augmented and non-augmented groups in surgical outcomes.

XEN® implantation: an effective strategy to stop glaucoma progression despite prior minimally invasive glaucoma surgery

Purpose

The aim of this study was to evaluate whether XEN® implantation is a reasonable and safe method to lower the intraocular pressure (IOP) and amount of medication for adult primary open-angle glaucoma (POAG) over a 3-year period. The influence of the type of anesthesia, previous glaucoma surgery, and postoperative interventions on the outcome were examined.

Methods

In this retrospective study, 96 eyes were included. XEN® implantation was performed as sole procedure under general (n = 86) or local anesthesia (n = 10). IOP and number of glaucoma medication were assessed preoperatively: day 1, week 6, month 3, 6, 12, 24, and 36. Further outcome parameters were Kaplan–Meier success rates, secondary intervention, and complication rates.

Results

IOP decreased from 20.7 ± 5.1 to 12.8 ± 2.5 mmHg at the 36-month follow-up (p < 0.001) and glaucoma therapy was reduced from 3.3 ± 0.8 to 1.2 ± 1.6 (36 months, p < 0.001). Transient postoperative hypotony was documented in 26 eyes (27.1%). General anesthesia resulted in a significant improvement of the survival rate compared to local anesthesia (77% vs. 50%, p = 0.044). Prior iStent inject®, Trabectome®, or SLT laser had no significant impact, such as filter bleb revision. The number of postoperative needlings had a significantly negative influence (p = 0.012).

Conclusion

XEN® implantation effectively and significantly lowers the IOP and number of glaucoma therapy in POAG in the 36-month follow-up with a favorable profile of side effects and few complications. In case of IOP, general anesthesia has a significant positive influence on the survival rate, whereas prior SLT or MIGS does not have significant impact.

A multicenter prospective comparative study evaluating cataract surgery and endoscopic cyclophotocoagulation either with or without iStent inject implantation in Brazilian patients with glaucoma

Purpose

Compare 12-month (12 M) safety and efficacy of endoscopic cyclophotocoagulation (ECP) + cataract surgery (Group 1) versus ECP + cataract surgery + iStent inject trabecular micro-bypass implantation (Group 2) in Brazilian patients with open-angle glaucoma (OAG).

Methods

This prospective, multicenter, comparative case series included patients with OAG and cataract who were randomized to receive treatment in Group 1 or Group 2. Outcomes included mean and percent reduction versus preoperative in intraocular pressure (IOP) and number of glaucoma medications; visual acuity; occurrence of adverse events; and rate of secondary surgeries.

Results

Preoperatively, Groups 1 and 2 had similar mean IOP (mean ± standard deviation 22.1 ± 3.6 and 22.0 ± 2.5 mmHg, respectively) and mean number of medications (3.3 ± 0.6 and 3.4 ± 0.6 medications, respectively). At all follow-up timepoints through 12 M, both groups achieved significant IOP and medication reductions versus preoperative (IOP p < 0.001 and number of medications p < 0.001 for both groups). At 12 M, IOP reductions were 24.2% (Group 1) and 43.6% (Group 2) (p < 0.001); mean medication reductions were 50.2% and 71.5%, respectively. Mean postoperative IOP and number of medications were higher in Group 1 than Group 2 (IOP p < 0.01 all visits, medication p < 0.01 at 6 M and 12 M). Adverse events were generally mild and infrequent in both groups.

Conclusion

Both treatment groups (ECP + phacoemulsification, with/without iStent inject implantation) achieved significant and safe reductions in IOP and medications versus preoperative in Brazilian OAG patients. Percent reductions were significantly greater, and mean IOP and medications were significantly lower, in the group receiving iStent inject.

Clinical trial registration (CTR)

CAAE project identification #20053019.5.0000.5078. Protocol #3.587.147. Clinical Trial Database of the Federal University of Goiás, Brazil. Registration Date: September 19, 2019.

Acute Attack of Glaucoma after Scleral Melting and Iris Blockage of the Surgical Ostium: A Case Report of a Complication Derived from a Mitomycin C Supplemented Trabeculectomy

Aim

To describe a case of an acute attack of glaucoma due to scleral melting in the area where a trabeculectomy was previously done. This condition resulted from the blockage of the surgical opening due to an iris prolapse in an eye that was previously supplemented with mitomycin C (MMC) during a filtering surgery and bleb needling revision.

Case description

A 74-year-old Mexican female with a prior glaucoma diagnosis who assisted to an appointment presenting an acute ocular hypertensive crisis after several months of adequately controlled intraocular pressure (IOP). Ocular hypertension had been regulated after undergoing a trabeculectomy and bleb needling revision; both supplemented with MMC. The severe IOP increase occurred due to uveal tissue blockage in the filtering site, related to melting of the sclera in the same area. The patient was successfully treated through the use of a scleral patch graft and the implantation of an Ahmed valve.

Conclusion

An acute attack of glaucoma associated with scleromalacia after trabeculectomy and needling has not been previously reported and is currently attributed to MMC supplementation. Nevertheless, the use of a scleral patch graft and further glaucoma surgery seems to be an efficient way to treat this condition.

Clinical significance

Even though this complication was appropriately managed with this patient, we want to prevent further cases like this through the judicious and careful use of MMC.

How to cite this article

Paczka JA, Ponce-Horta AM, Tornero-Jimenez A. Acute Attack of Glaucoma after Scleral Melting and Iris Blockage of the Surgical Ostium: A Case Report of a Complication derived from a Mitomycin C Supplemented Trabeculectomy. J Curr Glaucoma Pract 2022;16(3):199-204.

The Efficacy of Atelocollagen to Inhibit Fibrotic Proliferation in Tenon Tissue: In vitro Study

INTRODUCTION

The aim of the study was to evaluate the safety and efficacy of atelocollagen in preventing the fibrotic change of human tenon tissue induced by transforming growth factor β1 (TGFβ1).

METHODS

Primary cultured human Tenon's fibroblasts (HTFs) were incubated with TGFβ1 alone and with various concentrations of atelocollagen, respectively. Cell viability was measured by Cell Counting Kit-8 (CCK-8). The mRNA levels of α-smooth muscle actin (α-SMA), vimentin, fibronectin, zonular occludens scaffolding protein (ZO-1), cellular communication network factor 2 (CCN2), and interleukin 6 (IL-6) were measured by quantitative reverse transcription polymerase chain reaction, Western blot, and immunofluorescence analysis. Wound healing assay and collagen contraction assay were additionally evaluated for identifying the inhibitory effect of atelocollagen in HTFs. To elucidate the mechanism by which atelocollagen affects HTF proliferation, the phospho-extracellular-signal-regulated kinases (pERK)/total-extracellular-signal-regulated kinases (tERK), phospho-focal adhesion kinase (pFAK)/total-focal adhesion kinase (tFAK), and pSmad3/tSmad3 protein expression ratios were measured by Western blot.

RESULTS

The safety of atelocollagen in HTF was identified by CCK-8 analysis. The expression of α-SMA and vimentin in HTFs treated with 0.023% and 0.046% atelocollagen significantly decreased at both mRNA and protein levels, while that of ZO-1 in 0.046% atelocollagen increased compared with TGFβ1-treated cells. The protein expression of fibronectin, CCN2, and IL-6 in HTFs treated with 0.023% and 0.046% atelocollagen significantly decreased. The immunofluorescence microscopy of α-SMA and ZO-1 showed results similar to those of the Western blot. In the wound-scratch assays, cell migration was significantly attenuated in HTFs treated with 0.005% atelocollagen. Atelocollagen at 0.005, 0.011, and 0.023% significantly inhibited the gel contraction induced by TGFβ1 at both 24 h and 48 h. The increase in pERK/tERK and pSmad3/tSmad3 protein expression ratios in TGFβ1-treated HTFs significantly decreased after treatment with 0.023 and 0.046% atelocollagen.

CONCLUSION

Since atelocollagen gel effectively suppresses the proliferation of HTFs in TGFβ1-induced transdifferentiation, it may be a potential therapeutic agent in glaucoma surgery.

Intraocular Pressure Control Following Phacoemulsification in Eyes With Pre-existing Aurolab Aqueous Drainage Implant

PURPOSE

The aim was to investigate intraocular pressure (IOP) control after phacoemulsification in adult glaucomatous eyes with a functioning nonvalved Aurolab Aqueous Drainage Implant (AADI) compared with eyes that did not have cataract extraction post-AADI.

METHODS

In this retrospective study, we reviewed records of 47 patients (47 eyes) who had a clear corneal phacoemulsification after AADI placement with a minimum of 2 years of follow up. The control group included 89 patients (89 eyes) who had a functional AADI at 1 year, minimum of 3 years of follow up post-AADI implantation, and no cataract extraction. The main outcome measure was failure (IOP >21 mm Hg or increased by >20% from prephacoemulsification level requiring at least 1 additional glaucoma medication, IOP ≤5 mm Hg, reoperation for glaucoma, or loss of light perception vision).

RESULTS

The median interval between AADI and phacoemulsification was 11.5 months (range: 4 to 68 mo), and the mean follow-up time after phacoemulsification was 35.6±6.4 months. The cumulative probability of failure was 14% (95% confidence interval=6%-31%) in the phaco group and 6% (95% confidence interval=3%-13%) in the control group at 2 years (P=0.11). Mean IOP was reduced from 16.5±4.5 mm Hg preoperatively to 15.4±4.7 mm Hg at 2 years after phacoemulsification (P=0.10). Mean LogMAR visual acuity improved from 1.1±0.6 preoperatively to 0.6±0.7 at 2 years after phacoemulsification (P<0.001).

CONCLUSIONS

In eyes with a pre-existing AADI, phacoemulsification resulted in visual improvement without a significant rise in IOP or increased risk of AADI failure after 2 years follow up.

Characteristic Assessment of Angiographies at Different Depths with AS-OCTA: Implication for Functions of Post-Trabeculectomy Filtering Bleb

This study aimed to analyze the quantitative vascular biomarkers of filtering bleb function at different depths using anterior segment optical coherence tomography angiography (AS-OCTA). This cross-sectional study is registered on Clinicaltrails.gov (NCT 04515017). Forty-six eyes with primary open-angle glaucoma that had undergone trabeculectomy with mitomycin-C for more than six months were included. Vessel density (VD) and vessel diameter index (VDI) in the superficial layer (SL), Tenon’s layer (TL), and deep layer (DL) of the bleb were obtained. The VD and VDI were higher in the failure group (both p = 0.000). Significant correlations were found between the SL, TL, DL’s VDI, and IOP in the success group (p = 0.013, 0.016, 0.031, respectively). The VD of the TL and DL were related to IOP in the failure group (p = 0.012, 0.009). Tenon’s VD (TVD) and Tenon’s VDI (TVDI) correlated with IOP adjusting for TVD, TVDI, and the Indiana Bleb Appearance Grading Scale (IBAGS) (p = 0.009, 0.043) or Kenfeld grading system (KGS) (p = 0.011, 0.016). The area under curve (AUC) of the TVD, TVDI, IBAGS, and KGS to predict surgery failure were 0.960, 0.925, 0.770, and 0.850. AS-OCTA realized the quantitative evaluation of vessels, especially the invisible vascularity beneath the conjunctiva. TVD and TVDI as detected by AS-OCTA better reflected bleb function than conventional grading systems.

Effect of Prior Phacoemulsification Surgery in Trabeculectomy Surgery Outcomes

Purpose

Methods

Results

Conclusion

Long-term treatment success and safety of combined phacoemulsification plus excimer laser trabeculostomy: an 8-year follow-up study

PURPOSE

Combined phacoemulsification plus excimer laser trabeculostomy (phaco-ELT) is a minimally invasive surgery that effectively reduces intraocular pressure (IOP) in patients with glaucoma and a concomitant diagnosis of cataract. The aim of this study was to evaluate the long-term treatment success as well as safety of phaco-ELT over an 8-year follow-up period.

METHODS

Patients with a diagnosis of primary or secondary glaucoma or ocular hypertension and a visually significant cataract who underwent a combined phaco-ELT between January 1, 2008, and December 31, 2010, were included. Data for IOP, the number of IOP-lowering medications (meds), best-corrected visual acuity, complications, and subsequent surgeries to lower IOP were collected preoperatively (baseline) and intraoperatively as well as at 1 day, 1 week, 1 month, 3 months, 6 months, 9 months, 1 year, and every 6 months thereafter to 8 years postoperatively.

RESULTS

One hundred sixty-one eyes of 128 patients were included. After 8 years of follow-up, the long-term treatment success rate with IOP ≤ 21 mmHg was 50.2%. No serious intra- or postoperative complications occurred. The mean IOP decreased significantly from 19.3 (±4.8) mmHg at baseline to 15.4 (±3.2, p =0.0040) mmHg at 8 years. Additionally, meds remained below baseline after 8 years of follow-up and were reduced significantly for up to 4 years. Only 25.5% of the eyes required a subsequent surgery to lower IOP during the follow-up period.

CONCLUSION

Combined phaco-ELT is a safe procedure without serious intra- or postoperative complications, which has a positive long-term effect regarding IOP and meds. Remarkably, the mean IOP-lowering effect remained stable and was reduced ≥ 20% from baseline after 3 months for the remainder of the follow-up duration, whereas the number of meds was reduced significantly for up to 4 years. Furthermore, only 25.5% of the eyes required a subsequent surgery to control IOP throughout the whole follow-up of 8 years.

Management of Intraocular Pressure Elevation After CO2 Laser-Assisted Sclerectomy Surgery in Patients With Primary Open-Angle Glaucoma

Purpose: To report the safety and efficiency of carbon dioxide (CO₂) laser-assisted sclerectomy surgery (CLASS) in Chinese patients with primary open-angle glaucoma (POAG) and the management of unexpected postoperative intraocular pressure (IOP) elevation.

Methods: This was a prospective case series study. A total of 23 eyes from 23 patients with POAG who underwent CLASS were involved and followed-up for 12 months. The primary outcomes included the changes in best corrected visual acuity (BCVA), IOP, and medications before and after CLASS. The secondary outcomes were success rate and postoperative laser interventions.

Results: The mean age of the patient was 42.6 ± 16.0 years. There was no significant change in BCVA and visual field at baseline and 12 months after CLASS. The number of medications was significantly reduced after CLASS. The IOP was also significantly decreased and remained well controlled during the follow-up period, except for a transient elevation at 1 month postoperatively, due to the occurrence of peripheral anterior synechiae (PAS). Generally, 17 patients (73.9%) were treated with neodymium-doped yttrium aluminum garnet (Nd:YAG) laser synechiolysis to remove iris obstruction in the filtration site and seven patients (30.4%) underwent Nd:YAG laser goniopuncture to deal with scleral reservoir reduction. Only one patient (4.3%) received surgical repositioning due to iris incarceration. The complete success rate and total success rate at 12 months were 69.6 and 95.7%, respectively.

Conclusion: CLASS was a safe and effective approach for Chinese patients with POAG. Peripheral anterior synechiae (PAS), iris incarceration, and scleral reservoir reduction were common causes of unexpected postoperative IOP elevation. Individualized Nd:YAG laser intervention helps to improve the long-term outcomes after CLASS.

Electronically Monitored Corticosteroid Eye Drop Adherence after Trabeculectomy Compared to Surgical Success

OBJECTIVE

To compare electronically measured adherence with topical corticosteroid drops to outcomes of glaucoma surgery.

DESIGN

This prospective cohort study included eyes undergoing surgery from August 2019 to January 2021 and followed for up to 1 year.

PARTICIPANTS

All patients were recruited from the Glaucoma Center of Excellence at the Wilmer Eye Institute, Johns Hopkins. Eligible patients had either primary open angle or angle closure glaucoma, were ≥18 years old, and underwent either trabeculectomy (with or without cataract surgery) or tube-shunt implantation.

INTERVENTION

Patients were instructed on use of an eyedrop monitoring device (Kali Drop®), with knowledge that it would be used to record postoperative corticosteroid instillation in real time.

MAIN OUTCOMES

Adherence to a regimen of corticosteroid eye drops during the first 5 postoperative weeks; achievement of target intraocular pressure (IOP) at 6 weeks, 6 months to 1 year after surgery; and bleb morphology at 1 year.

RESULTS

Among 90 patients, adherence was 90 ± 14% overall and 81 ± 16% during q2h dosing. Target IOP was achieved at final visit (6 months or 1 year) in 81% (59/73) without reoperation. Eyes with a higher ratio of drops taken vs prescribed were significantly more likely to achieve target IOP at 6 months/1 year (p=0.05). Total adherence was better in younger persons, eyes with less field loss, and patients of one particular surgeon (p<0.03). Percent adherence during every 2 hours (q2h) dosing was higher in eyes with higher target IOP (p=0.01). No adherence outcome was significantly related to race, sex, bleb morphology, postoperative pain, or post-operative anterior chamber inflammation. Adherence values did not significantly correlate with adherence questionnaire data (predicted mean = 70 ± 17%, actual mean = 91 ± 13% adherent, p < 0.001).

CONCLUSION

Adherence with frequent postoperative eye drops was high and can be successfully monitored remotely. Surgical success was greater among eyes with nearly ideal adherence and was poorer in older persons and those with more advanced glaucoma.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT03402802.

Is canaloplasty with mitomycin c a safe procedure in myopic glaucoma?

PURPOSE

Myopic glaucoma patients display a considerable risk of complications following antiglaucomatous filtering surgery, e.g., trabeculectomy. Canaloplasty with mitomycin C may reduce this risk by avoiding massive overfiltration.

METHODS

We performed retrospective analysis of 31 eyes with myopia that underwent canaloplasty modified with mitomycin C in a consecutive single-surgeon case series. Annual data and success rates were analysed. Twenty-three myopic eyes that had received conventional trabeculectomy with mitomycin C were recorded as a comparison.

RESULTS

The 31 eyes with a follow-up of 40 ± 26 months after canaloplasty had a mean spherical equivalent of - 8.4 ± 4.5 dioptres. Intraocular pressure decreased from 32.3 ± 9.6 mmHg (range: 17 to 58) to 16.8 ± 8.1 mmHg (range: 5 to 44) 1 year after surgery (- 46%; p < 0.001) with a medication score reduction from 5 to 1.2 (p < 0.001). Qualified success rates (Criterion B: no revision surgery, IOP < 21 mmHg, IOP reduction > 20%) were 83% after 1 year and 61% at the 2nd and 3rd years. In 5 eyes (16%), early ocular hypotony (≤ 5 mmHg) was observed. Two eyes (7%) showed transient choroidal detachment and swelling. The 23 eyes that had received trabeculectomy had success rates (Criterion B) of 91% at the 1st and 86% at the 2nd and 3rd years. Hypotony occurred in 10 eyes (44%), and 4 eyes (17%) showed choroidal detachment or macular folds.

CONCLUSIONS

Postoperative complications related to overfiltration were less frequent after canaloplasty with mitomycin C. Midterm data proved good efficacy. Pressure reduction, success rates and rates of medication free patients were significantly higher in trabeculectomy compared to modified canaloplasty with mitomycin C.

A Modified Technique in Applying Sponge Soaked with Mitomycin C in Trabeculectomy

ABSTRACT

Trabeculectomy with adjunctive use of Mitomycin C (MMC) has been a benchmark for glaucoma filtration surgery for decades. However, there are many variations in the ways that the sponges soaked with MMC are applied during the trabeculectomy surgery. We herein describe our way of placing the MMC-soaked sponges to improve the safety and efficacy of the trabeculectomy. The sponges are placed vertically and posteriorly with the long side of the sponge perpendicular to the limbus, not parallel. This will reduce the size of the conjunctival wound at the limbus to preserve more virgin conjunctiva that can be used for repeated trabeculectomy when needed. This will also facilitate a more posteriorly directed flow of aqueous drainage that, in turn, may increase the success rate of the trabeculectomy. We have obtained encouraging results in our practice, and further large-scale randomized studies seem warranted.

Trabecular Microbypass Stent and Phacoemulsification in African American Patients With Open-angle Glaucoma: Outcomes and Effect of Prior Laser Trabeculoplasty

PRECIS

In African American patients with glaucoma, iStent/phacoemulsification lowered intraocular pressure and reduced glaucoma medication usage for up to 1 year, even in patients with prior selective laser trabeculoplasty (SLT).

PURPOSE

Currently, no studies have examined the outcomes of a trabecular microbypass stent and phacoemulsification in African American patients. Here, the authors investigate whether iStent/phacoemulsification decreases intraocular pressure (IOP) and/or medication usage in African American patients with glaucoma. They are also interested in whether prior SLT would affect outcomes of iStent/phacoemulsification.

PATIENTS AND METHODS

A multicenter, retrospective case series of eyes that underwent iStent/phacoemulsification between 2013 and 2017 with up to 1-year follow-up. Eyes with a confirmed diagnosis of glaucoma in African American patients were included. Eyes with neovascular glaucoma or closed angle glaucoma and eyes that underwent previous incisional glaucoma surgery were excluded.

RESULTS

Eighty-nine eyes were included in the study and data for 66 eyes were available at postoperative year 1 (POY1). IOP decreased from 18.3±5.7 mm Hg to 15.9±4.6 (P<0.001) and glaucoma medication usage decreased from 1.9±1.1 to 1.1±1.1 (P<0.001) at POY1. Eyes that underwent prior SLT experienced less of a decrease in IOP when compared with eyes without prior SLT, but IOP at POY1 was not significantly different between these groups. Both groups had a similar reduction in medication usage. The most common complications were IOP spikes on postoperative day 1 and microhyphemas.

CONCLUSIONS

In this cohort, there was a significant decrease in IOP and medication usage 1 year after iStent/phacoemulsification. iStent/phacoemulsification is an effective and safe treatment option in African American patients with glaucoma.

Outcome of Trabeculectomy with Collagen Matrix Implant versus Mitomycin C in Primary Glaucoma: A Comparative Study

Background:

Glaucoma is a serious vision-threatening condition appropriately called as the silent killer of sight. The effect of postoperative fibrosis on success of filtration surgeries requires modulation of the wound healing process.

Aim:

The aim of the study was to compare trabeculectomy augmented with collagen matrix implant with mitomycin C in primary glaucoma.

Materials and Methods:

This prospective, longitudinal, hospital-based, analytical, and interventional study was conducted on 36 eyes of 36 patients. Group 1 included 18 patients who underwent trabeculectomy combined with subconjunctival collagen matrix implant and Group 2 included 18 patients who underwent trabeculectomy augmented with intraoperative mitomycin C (0.04 mg/ml) for 2 min. Each patient underwent detailed ocular examination and comparison was drawn by recording intraocular pressure (IOP), bleb characteristics, and postoperative complications.

Results:

The cumulative success rates at the end of our study were similar in two groups, 94.44% in Group 1 and 88.89% in Group 2 (P = 1.000). The mean reduction in IOP at 24 weeks in Group 1 was 18.67 ± 7.59 mmHg and in Group 2 was 21.32 ± 5.84 mmHg. The reduction in IOP was similar between the two groups (P = 0.290). The mean fall in IOP was 56.46% in Group 1 and 64.70% in Group 2 at 24 weeks. Mean bleb score in Group 1 was 10.33 ± 1.23 and in Group 2 was 8.89 ± 1.41, and the difference was statistically significant (P = 0.002). Shallow anterior chamber, overfiltration, and hypotony were statistically higher in Group 2 than in Group 1 (P = 0.041, 0.041, and 0.046, respectively).

Conclusion:

Collagen matrix implant as an adjuvant to trabeculectomy is noble, safe, and effective option as compared to mitomycin C.

Comparison of 5-year outcomes between trabeculectomy combined with phacoemulsification and trabeculectomy followed by phacoemulsification: a retrospective cohort study

Background

We aimed to compare the outcomes of trabeculectomy combined with phacoemulsification and those of trabeculectomy followed by phacoemulsification.

Methods

A total of 141 patients with primary open-angle glaucoma, exfoliation glaucoma, and glaucoma secondary to uveitis glaucoma who underwent trabeculectomy followed by (n = 48) or combined with (n = 93) phacoemulsification were included. We analyzed data collected from the Collaborative Bleb-Related Infection Incidence and Treatment Study, a prospective cohort study conducted in 34 clinical centers that included 1249 eyes. The main outcome was the cumulative probability of success based on intraocular pressure (IOP) within 5 years. Surgical failure was defined as a case in which additional glaucoma surgery is required or one of the following criteria are met: preoperative IOP > 21 (A), > 18 (B), or > 15 mmHg (C). The secondary outcomes were cumulative probability of success, risk factors of surgical failure, and Δ visual acuity. However, the data on phacoemulsification during the 5-year follow-up were censored.

Results

No significant difference was found in the cumulative probability of success as the main outcome. When the data on phacoemulsification during the 5-year follow-up were censored, the probabilities of success of trabeculectomy followed by phacoemulsification were significantly higher for criteria A (p = 0.02), B (p <  0.01), and C (p <  0.01). Lower preoperative IOP, younger age, and trabeculectomy combined with phacoemulsification were associated with poorer outcome. Trabeculectomy followed by phacoemulsification had significantly worse Δ logMAR visual acuity at 6 and 12 months (p <  0.01).

Conclusion

The cumulative probability of success after trabeculectomy combined with or followed by phacoemulsification remained unchanged. Combining phacoemulsification with trabeculectomy adversely affected the cumulative probability of success after trabeculectomy. The visual acuity improvements observed in the early postoperative period after combining phacoemulsification with trabeculectomy disappeared within 5 years.

Augmented trabeculectomy-outcomes of first hundred versus second hundred surgeries of a fellowship-trained glaucoma surgeon

PURPOSE

We aim to compare the outcomes of trabeculectomy with mitomycin-C by a fellowship-trained glaucoma surgeon in the first hundred compared to second hundred surgeries.

PATIENTS AND METHODS

Retrospective review of 200 consecutive surgeries from May 2015 to January 2017. Primary outcomes were intraocular pressure (IOP) control and use of IOP-lowering medications. Success between first hundred (Group 1) and second hundred (Group 2) patients were reported using World Glaucoma Association guidelines. Kaplan-Meier survival demonstrated complete success and qualified success. Secondary outcome measures were postoperative complications, bleb interventions and additional procedures.

RESULTS

We found no statistical difference between the first hundred and second hundred patient's postoperative IOP at week 4 (p = 0.17), 3 months (p = 0.74), 6 months (p = 0.46), 12 months (p = 0.47), 18 months (p = 0.13) or at final follow up (p = 0.53). The mean final follow up period was 3.6 ± 0.7 years. Mean IOP reduction in Group 1 was from 27.1 ± 10.8 to 12.6 ± 7.1 (p < 0.0001) and Group 2 from 22.8 ± 8.4 to 11.3 ± 4.2 (p < 0.0001). Kaplan-Meier graphs showed no significant difference in complete success (p = 0.0693) or qualified success (p = 0.0866) between Group 1 and Group 2. Bleb interventions were not statistically significant between two groups. There was a significantly higher rate of complications with the first hundred patients (p < 0.0001).

CONCLUSION

Both first hundred and second hundred patient groups achieved statistically similar outcomes in long term IOP control. Significant reduction of complications was achieved in the second group of patients.

Factors Associated With Unqualified Success After Trabecular Bypass Surgery: A Case-control Study

PRECIS

An older age, a low number of baseline glaucoma medications, an early glaucoma stage, lower intraocular pressure (IOP) values during the first postoperative month, and combined surgery are possible predictors of unqualified success after a trabecular by-pass microinvasive glaucoma surgery (MIGS) procedure.

PURPOSE

The purpose of this study was to identify the potential predictors of unqualified success (IOP<18 mm Hg with no glaucoma medication) after trabecular by-pass MIGS.

MATERIALS AND METHODS

We designed a case-control study using logistic regression modeling that included all trabecular by-pass surgeries with at least 3 months of follow-up, performed at a single center from June 2017 to December 2019. Eyes that achieved an endpoint of unqualified success (dependent variable) were considered cases. All other eyes were used as the controls. Cases and controls were paired by sex and postoperative time. We tested the following independent variables: age, race, laterality (right eye or left eye), glaucoma stage, type of surgery (combined or stand-alone), type of trabecular bypass, intraoperative complications, baseline number of medications, baseline IOP, and postoperative IOP on days 1, 15, and 30. Additional analysis using IOP <15 mm Hg as a threshold and including eyes with at least 12 months of follow-up were performed.

RESULTS

One hundred ninety-four eyes were included in the analysis. We observed complete success in 56.7% of eyes. The mean follow-up time for the entire population was 12.3±6.8 months. All variables were considered in the first step of the modeling process; however, only age, day-15 IOP, day-30 IOP, baseline number of medications, glaucoma stage, and type of surgery remained until the completion of our model, with adequate significance (P<0.05). The additional analysis confirmed our results.

CONCLUSION

We identified that an older age, a low number of baseline glaucoma medications, an early glaucoma stage, lower IOP values during the first postoperative month, and combined surgery were associated with a higher chance of unqualified success at 12 months after a trabecular by-pass MIGS procedure.

ExPress mini shunt device with trabeculectomy surgery in patients with uncontrolled glaucoma of Middle Eastern descent

PURPOSE:

The aim of this study is to assess the efficacy and safety of ExPress mini shunt in glaucoma patients of Middle Eastern descent.

METHODS:

This is a prospective cohort study. Uncontrolled glaucoma patients were subjected to ExPress mini-shunt implant. Pre- and post-operative glaucoma clinical indices were measured and compared. Both intra- and postoperative complications and surgical success rates were assessed. In addition to comparing a group of combined ExPress mini-shunt implant with cataract surgery versus ExPress mini-shunt implant alone.

RESULTS:

A total of 35 eyes of 31 patients were involved. The most common type of glaucoma was primary open-angle glaucoma in 13 eyes (37.1%). Fourteen eyes (40.0%) were combined ExPress device with cataract surgery. The mean intraocular pressure (IOP) (±standard deviation) at the last visit dropped from 24.6 mmHg (±8.3) to 13.9 mmHg (±4.5). There was a significant reduction in the number of postoperative glaucoma medications from 3.0 ± 0.5 to 1.3 (±0.7). In cases combined with cataract extraction, the patients required fewer anti-glaucoma medications. Complete success was achieved in 22 eyes (63%) and qualified success was achieved in 9 eyes (26%), whereas 4 eyes (11%) were considered a failure. The two most common complications encountered were hypotony (28.6%) and hyphema (11.4%).

CONCLUSION:

Among the studied population of patients, ExPress offers IOP reduction that is comparable to reported rates following standard trabeculectomy. Postoperative hyphema was encountered at a slightly higher rate.

The Effect of Antiglaucoma Procedures (Trabeculectomy vs. Ex-PRESS Glaucoma Drainage Implant) on the Corneal Biomechanical Properties

The aim of this study is to investigate the effect of two antiglaucoma procedures, namely trabeculectomy and Ex-PRESS mini-shunt insertion on the biomechanical properties of the cornea. This is a prospective study. Thirty patients (30 eyes) were included in the study. Nineteen eyes had an Ex-PRESS shunt inserted (Group 1) and 11 had trabeculectomy (Group 2). The examination time points for both groups were one to three weeks preoperatively and at month 1, 6, and 12 postoperatively. Corneal biomechanical properties (corneal hysteresis (CH) corneal resistance factor (CRF)) were measured with the Ocular Response Analyzer (ORA). In group 1, CH was significantly increased at 6 and 12 months compared to baseline values. Corneal hysteresis was also higher at 1 month postoperatively, but this increase did not reach statistical significance. In group 2, the CH was significantly increased at all time points compared to the preoperative values. CRF decreased at all time points postoperatively compared to the preoperative values in both groups. The difference (preoperative values to postoperative values at all time points) of the CH and CRF between the two groups was also compared and no significant differences were detected between the two surgical techniques. Trabeculectomy and the EX-PRESS mini-shunt insertion significantly alter the corneal biomechanical properties as a result of the surgical trauma and the presence of the shunt in the corneal periphery. When compared between them, they affect the corneal biomechanical properties in a similar way.

Common and rare complications following filtering surgery for children with congenital glaucoma; a5 years study

PURPOSE

To determine the incidence of postoperative complications following combined trabeculotomy trabeculectomy with mitomycin C (CTTM) for congenital glaucoma (CG), in addition to documentation of some unusual complications and possible ways to manage these complications safely with minimal morbidity.

METHODS

A retrospective observational study was performed on 190 eyes with CG had a CTTM procedure.Included eyes were operated upon between February 2015 and February 2020 in Sohag University Hospitals. Medical records were reviewed and postoperative complications were reported. Incidence of postoperative complications and their management were the main outcome measures.

RESULTS

Early complications developed the form of shallow anterior chamber (AC) (16.3%), hyphema (10.5%), serous choroidal detachment (2%), hemorrhagic choroidal detachment (2%). Unusual and rare complications occurred in the form of iatrogenic Cushing syndrome, unilateral toxic keratopathy developed, vitreous hemorrhage (VH), intercalary staphyloma and decompression retinopathyLate complications included: high postoperative intraocular pressure (IOP) (16.5%), thin cystic blebs (13.1%), hypotony disc edema (2%), cataract (3.2%), one eye developed blebitis and one eye developed endophthalmitis.

CONCLUSION

Surgical management of CG is full of complications in early and late postoperative periods such as shallow AC, hyphema and thin cystic blebs. Some unusual and rare complications developed such as iatrogenic Cushing syndrome, unilateral toxic keratopathy, vitreous hemorrhage, intercalary staphyloma and decompression retinopathy. If identified early; all these complications could be managed properly leading to a successful and favorable outcome.

Comparison of the Efficacy and Safety of Trabeculectomy with Mitomycin C According to Concentration: A Prospective Randomized Clinical Trial

(1) Background: Mitomycin C (MMC) is commonly used during trabeculectomy. However, there is no consensus on which concentration should be used. We aimed to compare the efficacy and safety of 0.2 mg/mL and 0.4 mg/mL of MMC in eyes undergoing trabeculectomy. (2) Methods: Thirty-six eyes (36 glaucoma patients) were randomized to undergo a trabeculectomy with 0.2 mg/mL or 0.4 mg/mL of MMC. The success rate was evaluated according to three criteria: (A) intraocular pressure (IOP) ≤ 18 mmHg and IOP reduction ≥ 20%; (B) IOP ≤ 15 mmHg and IOP reduction ≥ 25%; (C) IOP ≤ 12 mmHg and IOP reduction ≥ 30%. Cox’s proportional hazard model was used to identify the predictive factors for failure. Immunohistochemical procedures for matrix metalloproteinase (MMP) were performed on Tenon’s tissue. Bleb morphology was evaluated. Safety was assessed based on the incidence of complications. (3) Results: Of the 36 eyes, 19 underwent trabeculectomy with 0.2 mg/mL of MMC and 17 with 0.4 mg/mL. The success rates were 75%, 67%, and 47% at 6 months for criteria A, B, and C, respectively. There were no significant differences between the two groups. High MMP-9 staining and low preoperative IOP were associated with failure (hazard ratio (HR), 5.556; p = 0.033, and HR, 0.936; p = 0.033). Complications included hypotony in two eyes (6%), hyphema in one eye (3%), and choroidal detachment in one eye (3%). (4) Conclusions: Trabeculectomy with 0.2 mg/mL and 0.4 mg/mL of MMC showed similar IOP-control effects to those recorded in previous studies, along with a low rate of complications. There was no significant difference in efficacy or safety between the 0.2 mg/mL and 0.4 mg/mL MMC groups.

Comparison of the Surgical Outcomes of Single-Site, Mitomycin C-Augmented Trabeculectomy Combined with Phacoemulsification versus Manual Small-Incision Cataract Surgery

Purpose

To compare the safety, efficacy, and outcome measures of a single-site, mitomycin C (MMC)-augmented trabeculectomy combined with phacoemulsification (PT) versus manual small-incision cataract surgery (MSICS) with the posterior chamber intraocular lens (PCIOL) implantation as a primary surgery in the patients with primary glaucoma coexistent with cataract.

Methods

From April 2015 to August 2017, medical records of all the patients who underwent combined cataract surgery with PCIOL and MMC augmented trabeculectomy were reviewed. One hundred and thirty-seven eyes met the inclusion criteria. Ninety-seven eyes which underwent PT with MMC were compared with forty eyes that underwent MSICS combined with trabeculectomy (MSICST) MMC. Outcome measures were best corrected visual acuity (BCVA), intraocular pressure (IOP), and number of anti-glaucoma medications (AGM). Complications, if any, were noted in both the groups.

Results

The mean follow-up period after surgery was 18.6 ± 7.7 months (range, 12-40 months). At the last follow-up visit, there was no statistically significant difference between the groups, in terms of mean logMAR BCVA (PT: 0.22 ± 0.31, MSICST: 0.21 ± 0.33, P = 0.8), mean IOP reduction (PT: 13.9 ± 2.98 mmHg, MSICST: 14.1 ± 4.12 mmHg, P = 0.8), and mean number of AGM (PT: 0.03 ± 0.8, MSICST: 0.025 ± 0.7, P = 0.8). Complications were few and transient. One eye in the PT group was considered as a failure and had to undergo needling, repeat trabeculectomy, and later, cyclodestructive procedure. None of the eyes in the MSICST group required an additional procedure for IOP reduction.

Conclusion

There was no difference in the mean IOP reduction, BCVA, and mean number of AGM between the two procedures, and both appeared to be safe and effective techniques as a primary surgery in the patients with coexistent cataract and glaucoma.

[Endophthalmitis after perforation of the conjunctiva by a glaucoma gel-stent implant]

Intraokulare Infektionen durch Abiotrophia defectiva sind sehr selten. Hier berichten wir von einer 57-jährigen Patientin, welche sich 3 Monate nach erfolgter komplikationsloser Kataraktoperation mit Implantation eines Glaukom-Gelstents am rechten Auge mit einer Abiotrophia-defectiva-assoziierten Endophthalmitis bei uns vorstellte. Die Patientin klagte zuvor über eine Rötung im Bereich der nasal oberen Bindehaut des rechten Auges sowie über Schmerzen 2 Wochen vor Auftreten der Endophthalmitis. Eine 2‑wöchige topische Steroidtherapie ohne Antibiotikaschutz brachte eine kurzfristige Besserung. Die Patientin stellte sich nun bei uns mit einem Hypopyon, einer akuten Visusverschlechterung und starken periokulären Schmerzen seit dem frühen Morgen vor. Der Gelstent hatte spontan die Konjunktiva perforiert. Es erfolgte die unmittelbare Therapie mit lokaler und systemischer Antibiose. Sechs Stunden danach wurde eine Pars-plana-Vitrektomie mit intraokularer Gabe von Antibiotika durchgeführt. Durch eine zeitnahe Therapie konnte in diesem Fall ein relativ benigner Verlauf erreicht werden. Im klinischen Alltag sollte bei Patienten, die sich nach glaukomchirurgischen Eingriffen mit akuter Visusverschlechterung und Schmerzen präsentieren, dringend an eine mögliche spontane Bindehautperforation und Late-onset-Endophthalmitis gedacht werden. Zudem ist zu empfehlen, dass eine unklare Konjunktivitis nach Glaukomchirurgie immer antibiotisch abgedeckt und engmaschiger kontrolliert werden sollte.

A pilot study for smartphone photography to assess bleb morphology and vasculature post-trabeculectomy

Purpose

The current grading systems used for bleb morphology assessment in patients post-trabeculectomy are based on standardized slit-lamp photographs and anterior segment imaging devices. The lack of availability of these expensive and non-portable devices in resource-deficient settings is a significant deterrent in their widespread utilization for proper post-operative management. The rapidly evolving utilization of smartphone photography has significantly benefited diagnostics of posterior segment disorders and is now being increasingly utilized for monitoring anterior segment pathologies as well as post-surgical course. In this study, we study a novel use of smartphones for bleb photography for assessing the morphological characteristics as vascularity and microcysts.

Methods

In this pilot, observational study, we compared the trabeculectomy bleb images of five subjects, obtained by iPhone X (dual lens) and iPhone 6S (single lens). We captured two image sets with both smartphones first with a focussed torchlight and then with a built-in flash video light.

Results

The images resulting from the newer iPhone X were substantially superior than those from iPhone 6S. For the 12-megapixel dual-camera set-up on the iPhone X, the 1 × lens resulted in better images than the 2 × lens with contrast and overall clarity of the area of interest. While the macro-lens attachment had promising results at 1 × zoom, there is no added advantage of the macro-lens attachment as it resulted in considerable loss of image quality at twice the zoom. Using a 20 D lens helped attain higher magnification and better framing as it reduced the focussing distance needed to get sharp images. The images obtained from both smartphones were of higher quality when illuminated from an external source when compared to the native iPhone flash due to even exposure and fewer autofocus artefacts.

Conclusion

Analyses of all image sets showed that the current generation in-built camera app on IOS and newer iPhone camera optics resulted in high-quality images of the ocular surface with high magnification without any loss in clarity.

Electronic supplementary material

The online version of this article (10.1007/s10792-020-01598-9) contains supplementary material, which is available to authorized users.

Long-Term Outcomes from an Intraoperative Bleb Needling Procedure Augmented with Continuous Infusion

PURPOSE

To investigate long-term outcomes of a modified bleb needling technique performed in the operating room in controlling intraocular pressure (IOP) and to report risk factors for procedure failure.

DESIGN

Retrospective, observational cohort study.

PARTICIPANTS

One hundred six eyes of 98 consecutive patients undergoing intraoperative bleb needling with a continuous infusion of balanced salt solution at the Wilmer Eye Institute, Johns Hopkins Hospital, in the setting of a failed trabeculectomy or express shunt, between May 2011 and December 2015.

METHODS

Postoperative data were collected between May 2011 and August 2019. Success was defined as achieving a previously determined target IOP regardless of (qualified success) or without (complete success) glaucoma medications. Patients who underwent additional glaucoma surgery were censored in the survival analysis.

MAIN OUTCOME MEASURES

Primary outcome measures included IOP, attainment of target IOP, and number of glaucoma medications used at different time points pre- and post-operatively.

RESULTS

Needling was performed in 106 eyes at an average of 4.3 years from the time of trabeculectomy (standard deviation [SD], 6.5 years) and an average baseline IOP of 20.7 mmHg (SD, 7.2 mmHg). Further glaucoma surgery was required for 33 eyes. We observed a 70% qualified success rate with a mean IOP lowering of 25% (95% confidence interval [CI], 13.8%-36.4%) at 1 year after surgery and a 52% qualified success rate and 44.3% reduction in IOP (95% CI, 34.9%-53.6%) at 5 years after surgery. Nearly half and a third of the eyes did not require medications after 1 and 5 years, respectively. The average medication reduction was 0.8 at year 1 (95% CI, 0.5-1.1) and 0.4 at year 5 (95% CI, -0.2 to 1.0). Postoperative complications were uncommon. Poorer outcomes were not associated with the age of the bleb but were more likely in Black patients.

CONCLUSIONS

Reductions in IOP were maintained in most patients over the long term using a modified bleb needling technique, despite an average time from trabeculectomy of over 4 years. No significant adverse events were observed. Bleb needling may defer or avoid more invasive procedures such as tube-shunts or repeat trabeculectomy.

Learning from the past: Mitomycin C use in trabeculectomy and its application in bleb-forming minimally invasive glaucoma surgery

Trabeculectomy has been performed since the mid-1960s and remains the gold standard for glaucoma surgery. Newer surgical options have evolved, collectively referred to as minimally invasive glaucoma surgeries. Despite producing large intraocular pressure decreases, full-thickness procedures into the subconjunctival space may be limited by fibrosis. Mitomycin C (MMC) and 5-fluorouracil have been in use with trabeculectomy with good evidence of significantly increased success at the cost, however, of an increased risk of complications. Off-label MMC application can be found in almost all clinical trials, including in combination with minimally invasive glaucoma surgeries. We explore current evidence for MMC use in trabeculectomy and how this may differ for minimally invasive glaucoma surgery devices and analyze the range of agents and doses that are used. Although we found that most studies could not show any correlation between MMC dosage and the surgical outcome, the success rates with the Xen® microshunt seemed to be higher when using 20 mcg of MMC than when using 10 mcg. Certain important methodological considerations make this hard to confirm definitively, and other factors such as placement of the device may play a more substantial role. For the PreserFlo® microshunt, preliminary data suggest higher success rates with higher MMC dosage at the cost of higher device-related adverse events and reoperations. Although the ideal dose still needs to be established, it seems very likely that MMC provides significant improvement in outcomes in bleb-forming minimally invasive glaucoma procedures.

Intraoperative injection versus sponge-applied mitomycin C during trabeculectomy: One-year study

Purpose

To determine the safety and efficacy of mitomycin C (MMC) injection versus sponge during trabeculectomy.

Methods

It is a prospective analysis of patients who underwent trabeculectomy with MMC and followed up for 1 year, divided into two groups, namely, group 1- injection (n = 21), group 2-> sponge (n = 21). The same concentration of MMC was used for both groups. Inclusion criteria were trabeculectomies with MMC for intraocular pressure (IOP) control in eyes with glaucoma (primary + secondary) with a follow-up of 1 year.

Results

Mean preoperative IOP in group 1 was 29.00 ± 11.92 mmHg and group 2 was 25.87 ± 11.09 mmHg, which reduced to 12.19 ± 4.03 and 15.56 ± 10.72 mmHg at final visit with P value of 0.0002 and 0.001, respectively. Mean preoperative number of antiglaucoma medications was 2.4 ± 0.87 in group 1 and 2.3 ± 0.96 in group 2, which reduced to 0.38 ± 0.5 and 0.91 ± 0.85 with P value of 0.001 and 0.0003, respectively. The complete success rate was 52.4% in the injection group and 26.1% in the sponge group at end of 1 year. Overall, success rate (complete + qualified) was 90.5% and 87% in group 1 and group 2 at final visit. All major complications were encountered in sponge group. 1 (11.1%) patient developed choroidal detachment and one had malignant glaucoma which got resolved by medical management. 33.3% cases had encapsulated bleb which received bleb needling. 44.4% cases underwent Argon laser suture lysis postoperatively.

Conclusion

The MMC injection may be as safe and as effective as conventional sponge application with comparable estimated complete treatment success.

Success of combined cataract extraction plus excimer laser trabeculotomy exceeds that of combined ab interno trabeculectomy with the trabectome or cataract extraction alone

PURPOSE

To determine the efficacy of cataract surgery alone and combined with two minimally invasive glaucoma surgery (MIGS) procedures (phaco-ELT and phaco-aiT).

METHODS

Data was collected from 12/2007 to 02/2012 in this retrospective, non-randomized, comparative single surgery center study. Reduction in IOP and hypotensive medication (AGD), change in visual acuity, success rates, and complications were computed by comparing preoperative data with data at 1 year postoperatively.

RESULTS

A total of 245 eyes of 245 subjects were included. Study eyes underwent phaco alone (38 eye) or combined phaco-ELT (105 eye) and phaco-aiT (102 eye). Phaco alone, combined phaco-ELT, and combined phaco-aiT lowered IOP by 1.5 ± 4.0 mmHg, 4.3 ± 5.6, and 5.3 ± 4.5 mmHg, respectively (P < 0.01). Survival time of phaco-ELT outreached survival time of phaco alone and combined phaco-aiT (20.6 ± 1.0 vs. 13.2 ± 0.4 and 12.9 ± 0.6 month, respectively). No serious complications or adverse events occurred. None of the cases required a subsequent procedure within the first year to lower IOP further.

CONCLUSIONS

All three surgical procedures lowered IOP and reduced medication. However, the IOP-lowering efficacy of the two combined MIGS procedures exceeded the effect of phaco alone. A combined phaco and MIGS procedures seem reasonable to consider whenever a cataract surgery in an eye with glaucoma or ocular hypertension is considered. In addition, the combined MIGS procedure effectively lowers IOP whenever a target IOP in the mid-teens is sufficient. In this study, the nonthermal phaco-ELT procedure showed superior efficacy at 1 year over phaco alone and phaco-aiT in the Kaplan-Meier statistics.

Trabeculectomy followed by phacoemulsification versus trabeculectomy alone: The Collaborative Bleb-Related Infection Incidence and Treatment Study

PURPOSE

This study aims to compare the rate of surgical failure after trabeculectomy followed by phacoemulsification vs trabeculectomy alone for 5 years.

METHOD

A total of 1,098 eyes of patients with glaucoma who underwent trabeculectomy with mitomycin C at 34 clinical centers included in CBIITS were analyzed. During follow-up, some eyes were treated with phacoemulsification because of cataract progression. The patients were divided into the "trabeculectomy followed by phacoemulsification" and "trabeculectomy alone" groups, and surgical probabilities were compared. Surgical failure was defined on the basis of mean IOP as follows; < 20% reduction in preoperative IOP or IOP ≥ 21 mmHg (criterion A), IOP ≥ 18 mmHg (criterion B), or IOP ≥ 15 mmHg (criterion C).

RESULT

In total, 40 eyes were treated with trabeculectomy followed by phacoemulsification and 208 with trabeculectomy alone. Preoperative intraocular pressure was 22.1 ± 8.7 mmHg in the trabeculectomy followed by phacoemulsification group and 20.5 ± 6.3 mmHg in trabeculectomy alone group (P = 0.47). The 5-year cumulative probabilities of success in the trabeculectomy followed by phacoemulsification and trabeculectomy alone groups were respectively 40.0% and 59.1% for criterion A (P = 0.01), 35.0% and 52.9% for criterion B (P = 0.01), and 25.0% and 37.5% for criterion C (P = 0.08). Cox proportional hazards regression model indicated that shorter time gap between trabeculectomy and phacoemulsification was associated with surgical failure.

CONCLUSION

Phacoemulsification following trabeculectomy adversely affects surgical outcomes. In particular, a shorter time gap between trabeculectomy and phacoemulsification reduces the probability of success.

Postoperative adjunctive bevacizumab versus placebo in primary trabeculectomy surgery for glaucoma

AIM

To compare the effectiveness of postoperative adjunctive use of subconjunctival bevacizumab in altering the outcome of primary trabeculectomy in terms of sustained lowering of intraocular pressure (IOP) and reduction of postoperative bleb vascularization and fibrosis.

METHODS

A prospective, one center, randomized, placebo-control study. Fifty-nine patients (59 eyes) with uncontrolled IOP under maximal tolerated medical treatment (MTMT) were recruited. A primary trabeculectomy with mitomycin C (MMC) was done and the patients were randomized to either postoperative subconjunctival injection of bevacizumab (1.25 mg/0.05 mL) or balanced salt solution (BSS). Forty-seven patients (47 eyes) completed at least one year of follow up and were included in the study. The main outcome measure was the IOP, and secondary outcome measures include bleb morphology, vascularization, and fibrosis, as well as the need for glaucoma medications and 5-fluorouracil (5-FU) needling.

RESULTS

At 1-year follow up, there was no significant difference between groups for IOP (P=0.65), bleb morphology (P=0.65), and the need for glaucoma medications (P=0.65) or 5-FU needling requirements (P=0.11). However, the bevacizumab group had a higher rate of success results, lower use of glaucoma medications after surgery, and optimal bleb aspect in more patients, but more 5-FU needling procedures required.

CONCLUSION

A bigger sample size is needed in order to determine whether the differences found in the bevacizumab group are statistically significant.

Endophthalmitis Following XEN Stent Exposure

BACKROUND

XEN45 Gel stents are in their infancy, and clinical expertise with microsurgical glaucoma devices are increasing. The soft flexible nature of the XEN stent together with its malleability under the conjunctival tissue should negate any risk of exposure of the XEN45 stent (XEN). However, we report a case in which sight-threatening endophthalmitis was the presenting feature of this complication.

CASE REPORT

We present a case of uncomplicated XEN implantation that developed endophthalmitis 4 months after surgery. She gave an 8-day history of diarrhea before presentation. She was noted to have exposure of the XEN stent at the point of entry of the XEN into the subconjunctival space. The stent was removed, pars plana vitrectomy was carried out, and intravitreal antibiotics were administered. Achieving low intraocular pressures, bearing in mind her preservative allergy, became a challenge, as we struggled to manage her advanced glaucoma medically. A CyPass Micro-Stent was subsequently inserted to control the intraocular pressure.

CONCLUSIONS

Episodes of XEN stent exposure may not be so isolated. We postulate that poor handwashing transmitted the causative organism to the exposed stent, which then resulted in endopthalmitis. We would like to highlight a few learning points from this case.