Safety and Efficacy of the Preserflo® Microshunt in Refractory Glaucoma: A One-Year Study

Purpose: To evaluate the safety and efficacy of Preserflo^® microshunt implantation in eyes with refractory glaucoma. Methods: In this retrospective study, a cohort of patients who underwent Preserflo^® microshunt implantation between April 2019 and August 2020 for refractory glaucoma were evaluated. At the time of surgery, all eyes had uncontrolled intraocular pressure (IOP) despite maximally tolerated medical therapy and at least one previous failed glaucoma filtering surgery. The primary outcome was a complete success, defined as postoperative IOP ≤ 21 mm Hg with an IOP reduction ≥ 20% and no repeat filtering surgery. The secondary outcome was qualified success, defined as a complete success with the use of antiglaucoma medications. The rates of needling, bleb repair, and postoperative complications were also recorded. Results: Forty-seven eyes with a mean preoperative IOP of 30.1 ± 7.1 mm Hg and a mean of 3.4 ± 1 glaucoma medications were included. The mean number of previous surgeries prior to microshunt implantation was 2.3 ± 1.3. After 1 year, the mean IOP was significantly reduced to 18.8 ± 4.6 mm Hg, with the mean number of medications significantly reduced to 1.4 ± 1.2. Complete success was achieved in 35% of eyes, and a qualified success in 60% of eyes. A decrease in IOP of at least 30% was found in 55% of eyes. Needling or bleb repair was performed in 49% of eyes. Complications were minimal and transient, except for one eye which presented with tube extrusion, and another eye with a transected tube. A repeat glaucoma surgery had to be performed in 17% of eyes. Conclusions: The Preserflo^® Microshunt provided moderate success but a significant reduction in IOP, with a good safety profile after one year of follow-up in eyes at high risk for failure of filtering surgery.

Refractive Changes after Glaucoma Surgery-A Comparison between Trabeculectomy and XEN Microstent Implantation

Best-corrected visual acuity often decreases temporarily or permanently after trabeculectomy (TE). The purpose of this study was to compare visual acuity and refractive changes after TE or XEN microstent implantation (XEN) in primary open-angle glaucoma (POAG) or pseudoexfoliation glaucoma (PEX) cases naïve to prior glaucoma surgery over a 24-month follow-up period. We analyzed 149 consecutive glaucoma patients who received either TE or XEN because of medically uncontrollable POAG or PEX. Intraocular pressure (IOP), IOP-lowering medication use, subjective and objective refraction and best-corrected visual acuity were evaluated. In addition, surgically induced astigmatism (SIA) was calculated and compared using the vector analysis method described by Jaffe and Clayman. A total of 93 eyes (85 POAG; 8 PEX) were treated with TE and 56 eyes (50 POAG; 6 PEX) with XEN. After 24 months, the mean IOP and number of IOP-lowering medications used decreased significantly after TE (p < 0.01) and XEN (p < 0.01). In the TE group, mean best-corrected visual acuity (BCVA) changed from 0.16 ± 0.26 to 0.23 ± 0.28 logMAR (p < 0.01) after 24 months, while mean BCVA did not change significantly in the XEN group (preoperative: 0.40 ± 0.50 logMAR, postoperative: 0.36 ± 0.49 logMAR; p = 0.28). SIA was almost the same in both groups at the end of the 24-month follow-up period (0.75 ± 0.60 diopters after TE and 0.81 ± 0.56 diopters after XEN; p = 0.57). In addition, there was no significant correlation between SIA and the observed BCVA changes or SIA and IOP reduction 12 or 24 months after TE or XEN. Our results demonstrate that TE and XEN are effective methods for reducing IOP and IOP-lowering medication use. The SIA was nearly similar in both groups. The SIA does not seem responsible for the decreased visual acuity after TE.

Manual small-incision cataract surgery and glaucoma - A dilemma of the duo

Both cataract and glaucoma significantly affect the quality of life of an individual and they are often found to coexist, either primarily or secondary to one another. Clear-cut guidelines are not available for this subgroup of coexistent morbidities. Through this article, we attempt to discuss the risks and benefits of staged and combined surgery, their short- and long-term effects on the intraocular pressure and pre and postoperative management. The indication and type of surgery will depend on the type, severity and control of glaucoma, and the clinical significance of cataract; and the surgical outcome on the surgical technique used, site of surgery, use of anti-fibrotic agents, and most importantly, the surgeon's skill and experience.

Surgical Treatment of a Patient with Recurrent Bleb Leak and Glaucoma: Bleb Excision Combined with Gonioscopy-Assisted Transluminal Trabeculotomy

Here we present a case of intermittent bleb leakage with increased intraocular pressure (IOP) during recovery periods that was treated with gonioscopy-assisted transluminal trabeculotomy (GATT) combined with avascular bleb excision. A 60-year-old woman exhibiting simultaneous leaking bleb and glaucoma underwent GATT and bleb revision. At her final visit, the bleb leakage had resolved and IOP was under control without any further antiglaucoma medication. GATT may be useful for glaucoma patients exhibiting intermittent bleb leakage after failed trabeculectomy.

Gonioscopic angle evaluation and its correlation with graft survival and post-operative ocular hypertension in patients of Descemet's stripping endothelial keratoplasty

Purpose

To evaluate the gonioscopic changes in patients receiving Descemet's stripping endothelial keratoplasty (DSEK) without pre-existing ocular hypertension (OHT) and to report its correlation with post-surgery OHT, graft survival, and visual outcomes.

Methods

Adult patients who underwent DSEK surgery from April 2014 to March 2018 with at least 2 years of follow-up were analyzed in this retrospective study. Demographic details, indication of DSEK, necessary anterior and posterior segment findings, and the post-DSEK OHT details were documented.

Results

A total of 58 patients (23 males and 35 females) with a mean age of 61.44 ± 8.8 years were included in the study. The most common etiology for DSEK surgery was pseudophakic bullous keratopathy in 47 eyes (81.03%). A total of 22.41% (13/58) eyes showed elevated intra-ocular pressure (IOP) following DSEK surgery. The most common cause of IOP elevation was steroid-induced OHT in seven eyes (12.06%). Gonioscopy examination revealed areas of peripheral anterior synechiae (PAS) in 17 (29.3%) eyes. OHT was found in 4/17 (23.5%) eyes having PAS. Three of these cases required trabeculectomy + goniosynechiolysis (GSL), and the fourth case required GSL alone to control IOP. These four cases also required repeat DSEK for failed grafts. The mean pre-operative best corrected visual acuity was 1.62 logMAR (range 1.17-1.77), which gradually improved to 0.79 logMAR (range 0.3-1.77) after 2 years (p < 0.00001).

Conclusion

PAS was found to be an important factor associated with post-DSEK ocular hypertension in our study. OHT in PAS cases required definitive surgical treatments to control IOP. It adversely affected the graft survival and in turn affected visual outcomes also.

Comparison of Outcomes From Delayed-Onset Bleb-Related Endophthalmitis Treated With Pars Plana Vitrectomy Versus Vitreous Biopsy

PRCIS

Bleb-related endophthalmitis (BRE) is a serious complication of glaucoma filtration surgery. The current study reports similar visual and intraocular pressure (IOP) outcomes in eyes treated with pars plana vitrectomy (PPV) compared with vitreous biopsy and injection of intravitreal antibiotics (TI).

PURPOSE

The purpose of this study was to investigate the isolated organisms, visual acuity (VA), and IOP outcomes associated with delayed-onset BRE in eyes treated with PPV versus TI.

PATIENTS AND METHODS

A retrospective chart review was conducted at the Bascom Palmer Eye Institute (Miami, Florida) and the University of Florida (Gainesville, FL) identifying patients treated for BRE with at least 1 month of follow-up from the inception of an electronic health record (2014 and 2011, respectively) through 2021. All patients had undergone bleb-forming glaucoma surgery at least 1 month before endophthalmitis diagnosis.

RESULTS

Thirty-nine eyes from 39 patients (33 from Bascom Palmer, 6 from University of Florida) were included. Trabeculectomy was performed in 34 of 39 eyes (87.2%). Streptococcus species (9 eyes, 23.1%) and Staphylococcus species (8 eyes, 20.5%) were the most common isolated organisms and were similar in both treatment groups ( P =0.49). Baseline VA was worse in the PPV group (logarithm of the minimum angle of resolution: 2.51 vs. 2.16, P =0.04), but VA at last follow-up was similar ( P =0.48) in both groups. After recovery from BRE, the average IOP in the PPV group was 15.1 mm Hg on 0.9 IOP-lowering medications compared with 12.6 mm Hg on 1.2 medications in the TI group (IOP: P =0.56; medications: P =0.80). Additional glaucoma surgery was performed in 44.4% of the PPV eyes and 16.7% of the TI eyes ( P =0.09).

CONCLUSION

In eyes with delayed-onset BRE, isolated organisms, visual outcomes, and IOP control were similar after initial PPV compared with TI.

Laser trabeculoplasty for open-angle glaucoma and ocular hypertension

BACKGROUND

Open-angle glaucoma (OAG) is an important cause of blindness worldwide. Laser trabeculoplasty, a treatment modality, still does not have a clear position in the treatment sequence.

OBJECTIVES

To assess the effects of laser trabeculoplasty for treating OAG and ocular hypertension (OHT) when compared to medication, glaucoma surgery or no intervention. We also wished to compare the effectiveness of different laser trabeculoplasty technologies for treating OAG and OHT.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (which contains the Cochrane Eyes and Vision Trials Register) (2021, Issue 10); Ovid MEDLINE; Ovid Embase; the ISRCTN registry; LILACS, ClinicalTrials.gov and the WHO ICTRP. The date of the search was 28 October 2021. We also contacted researchers in the field.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) comparing laser trabeculoplasty with no intervention, with medical treatment, or with surgery in people with OAG or OHT. We also included trials comparing different types of laser trabeculoplasty technologies.

DATA COLLECTION AND ANALYSIS

We used standard methods expected by Cochrane. Two authors screened search results and extracted data independently. We considered the following outcomes at 24 months: failure to control intraocular pressure (IOP), failure to stabilise visual field progression, failure to stabilise optic neuropathy progression, adverse effects, quality of life, and costs. We graded the 'certainty' of the evidence using GRADE.

MAIN RESULTS

We included 40 studies (5613 eyes of 4028 people) in this review. The majority of the studies were conducted in Europe and in the USA. Most of the studies were at risk of performance and/or detection bias as they were unmasked. None of the studies were judged as having low risk of bias for all domains. We did not identify any studies of laser trabeculoplasty alone versus no intervention. Laser trabeculoplasty versus medication Fourteen studies compared laser trabeculoplasty with medication in either people with primary OAG (7 studies) or primary or secondary OAG (7 studies); five of the 14 studies also included participants with OHT. Six studies used argon laser trabeculoplasty and eight studies used selective laser trabeculoplasty. There was considerable clinical and methodological diversity in these studies leading to statistical heterogeneity in results for the primary outcome "failure to control IOP" at 24 months.  Risk ratios (RRs) ranged from 0.43 in favour of laser trabeculoplasty to 1.87 in favour of medication (5 studies, I2 = 89%). Studies of argon laser compared with medication were more likely to show a beneficial effect compared with studies of selective laser (test for interaction P = 0.0001) but the argon laser studies were older and the medication comparator group in those studies may have been less effective. We considered this to be low-certainty evidence because the trials were at risk of bias (they were not masked) and there was unexplained heterogeneity. There was evidence from two studies (624 eyes) that argon laser treatment was associated with less failure to stabilise visual field progression compared with medication (7% versus 11%, RR 0.70, 95% CI 0.42 to 1.16) at 24 months and one further large recent study of selective laser also reported a reduced risk of failure at 48 months (17% versus 26%) RR 0.65, 95% CI 0.52 to 0.81, 1178 eyes). We judged this outcome as moderate-certainty evidence, downgrading for risk of bias. There was only very low-certainty evidence on optic neuropathy progression. Adverse effects were more commonly seen in the laser trabeculoplasty group including peripheral anterior synechiae (PAS) associated with argon laser (32% versus 26%, RR 11.74, 95% CI 5.94 to 23.22; 624 eyes; 2 RCTs; low-certainty evidence); 5% of participants treated with laser in three studies of selective laser group had early IOP spikes (moderate-certainty evidence). One UK-based study provided moderate-certainty evidence that laser trabeculoplasty was more cost-effective.  Laser trabeculoplasty versus trabeculectomy Three studies compared laser trabeculoplasty with trabeculectomy. All three studies enrolled participants with OAG (primary or secondary) and used argon laser. People receiving laser trabeculoplasty may have a higher risk of uncontrolled IOP at 24 months compared with people receiving trabeculectomy (16% versus 8%, RR 2.12, 95% CI 1.44 to 3.11; 901 eyes; 2 RCTs). We judged this to be low-certainty evidence because of risk of bias (trials were not masked) and there was inconsistency between the two trials (I2 = 68%). There was limited evidence on visual field progression suggesting a higher risk of failure with laser trabeculoplasty. There was no information on optic neuropathy progression, quality of life or costs. PAS formation and IOP spikes were not reported but in one study trabeculectomy was associated with an increased risk of cataract (RR 1.78, 95% CI 1.46 to 2.16) (very low-certainty evidence).

AUTHORS' CONCLUSIONS

Laser trabeculoplasty may work better than topical medication in slowing down the progression of open-angle glaucoma (rate of visual field loss) and may be similar to modern eye drops in controlling eye pressure at a lower cost. It is not associated with serious unwanted effects, particularly for the newer types of trabeculoplasty, such as selective laser trabeculoplasty.

Evaluation of Sudden Visual Loss and Central 10-Degree Visual Field Change Following Glaucoma Surgery in Severe and End-Stage Eyes

Objectives

The purpose of the study was to evaluate the sudden visual loss and central 10-degree visual field (VF) change following glaucoma surgery in eyes with severe and end-stage glaucoma.

Methods

This was a single-center retrospective study. The charts of patients with severe and end-stage glaucoma who had undergone trabeculectomy and Ahmed glaucoma valve (AGV) implantation surgery were reviewed. Patients who had 10-2 Humphrey VF automated (HVFA) at follow-up were included and classified into two following groups: With split fixation on 10-2 HVFA before surgery split fixation group (SFG) and those without split fixation (WSFG).

Results

The data of 37 patients in SFG and 28 patients in WSFG were reviewed. The mean follow-up duration was 2.06±0.24 years in SFG and 2±0.3 years in WSFG. 10-2 HVFA revealed that SFG had a mean MD -25.8±5.2 dB preoperatively and -25.2±1.1 dB (p=0.18) at last visit, WSFG had a mean MD -9.8±4.8 dB preoperatively and -10.8±1.5 dB at last visit (p=0.10). In SFG, the mean intraocular pressure (IOP) decreased from 30.1±9.5 mmHg to 12.3±0.62 mmHg (p<0.001), and in WSFG, the mean IOP decreased from 30±6.9 mmHg to 12.3±0.90 mmHg at last visit (p<0.001). There was no statistical difference for visual acuity of both the groups at the follow-up (p=0.30 and p=0.70). In SFG, one patient had wipe-out phenomenon who had undergone AGV surgery.

Conclusion

Although wipe-out phenomenon was a rare complication, it can develop not only after trabeculectomy but also after AGV surgery, and patients with split fixation and severe and end-stage glaucoma were at risk for this phenomenon regardless of the type of surgery. Both trabeculectomy and AGV surgery appear to provide stability of the central 10° VF.

Glaucoma Treatment Outcomes in Open Angle Glaucoma Patients of African Descent

Open angle glaucoma (OAG), characterized by structural changes to the optic nerve head and retinal nerve fiber layer, is a progressive multifactorial optic neuropathy and a leading cause of irreversible blindness globally. Currently, intraocular pressure is the only modifiable risk factor; however, others have been identified, including genetics and race. Importantly, OAG is much more prevalent in persons of African descent (AD) compared with those of European descent (ED). OAG patients of AD are also known to have a more severe course of the disease, a finding potentially explained by structural and/or vascular differences within eye tissues. In addition, disparities in treatment outcomes have been identified in OAG patients of AD. Specifically, prostaglandin analogues have been suggested to be more effective in patients of AD than in those ED, while beta-adrenergic receptors have been suggested to be less effective, although the evidence is inconsistent. AD has also been identified as a risk factor for trabeculectomy failure while laser trabeculoplasty has been conversely found to be very effective in lowering intraocular pressure in patients of AD. Alternative surgical options, including Ex-Press shunt implantation, viscocanalostomy, and canaloplasty are promising in equivalence but require further research to evaluate disparity in outcome properly. In addition to treatment outcomes, social disparities affecting clinical care also exist for AD persons in the form of reduced adherence, access, and choice. Overall, data suggest the need for properly designed prospective trials with AD populations as a primary focus to identify the potential mechanisms driving disparities in treatment and address overall potential bias in glaucoma management.

How Reliable and Popular are Trabeculectomy Videos on Youtube?

PURPOSE

Evaluating the quality, dependability, and popularity of YouTube videos about trabeculectomy.

METHODS

A simulated user search for trabeculectomy videos on YouTube was conducted using the keywords "trabeculectomy, trabeculectomy surgery for glaucoma, and trabeculectomy surgery." Hundred out of the one hundred and fifty videos met the criteria and were analyzed. To assess quality and reliability, each video was evaluated by two independent reviewers using the DISCERN (scale, 1-5), Journal of the American Medical Association (JAMA; scale, 0-4), and Global Quality (GQ; scale, 1-5) criteria. The popularity of the videos was evaluated by Video Power Index (VPI). Videos were further classified into three groups based on the source of their upload.

RESULTS

Of the 100 analyzed videos, 50 were uploaded to the system by doctors, 40 by health institutions and 10 by patients. Fifty-seven percent are videos with surgical content. The mean DISCERN score was 44.84 ± 8.14 the mean JAMA score was 2.08 ± 0.67, and the mean Global Quality score was 2.02 ± 0.72. Although some videos provided adequate information, the majority of the videos were rated as fair. While the DISCERN, JAMA, GQS scores were statistically higher in videos uploaded by doctors than in videos uploaded by patients (P < 0.01), VPI was higher in videos uploaded by patients (P = 0.003). Nonsurgical videos had the highest rate of likes and comments (P < 0.05). No substantial difference in scoring was observed between the 2 independent reviewers (P < 0.05).

CONCLUSION

Videos with high popularity had low information quality and reliability. This situation presupposes video sharing in a more understandable language for patients.

A systematic approach to the management of microspherophakia

Microspherophakia is a rare developmental abnormality of the crystalline lens with a myriad of ocular and systemic associations. Glaucoma is a serious complication associated with this disorder. Early identification of the disease, timely visual rehabilitation, and appropriate management of the lens and glaucoma can help us prevent blindness from this condition. Multidisciplinary care with lifelong follow-up is recommended, as this typically affects the younger population. Current treatment protocols for this condition are mainly based on case reports and retrospective studies with shorter follow-up. Due to the rarity of this disease, designing a large randomized controlled trial to identify the merits and demerits of each management strategy is challenging. With cataract, glaucoma, and vitreoretinal specialists, each having their preferred way of managing microspherophakic lenses, we decided to do a comprehensive review of the existing literature to devise an integrated approach toward effective management of these patients. This review will collate all evidence and provide a very practical decision-making tree for its management.

Combined central retinal artery and vein occlusion following trabeculectomy

Retinal vascular events may occur as rare complications of glaucoma procedures due to various factors, including exacerbation of ischemia in patients with pre-existing vascular comorbidities, toxic effect of mitomycin-C, and decompression retinopathy. We present the case of a 47-year-old hypertensive male who underwent trabeculectomy for advanced glaucoma in his right eye. At 3 weeks postoperatively, he presented with a drop in visual acuity to light perception with a spike in intraocular pressure. On examination, there was increased bleb vascularity as well as rubeosis. Fundoscopy revealed findings consistent with both central retinal artery occlusion and central retinal vein occlusion. Combined central retinal artery and vein occlusion is a rare retinal vascular condition. Neovascular glaucoma can occur as a sequelae of the ischemic process in the retina. Despite treatment, there is a poor visual prognosis, with the affected eye usually becoming blind from optic atrophy and neovascularization.

Surgical Advancement of Tenon's Layer During Trabeculectomy Improves Bleb Morphology

Trabeculectomy surgery remains the gold standard incisional glaucoma surgical procedure in many practices, particularly for patients requiring intraocular pressure (IOP) in the low teens or below. However, trabeculectomy surgery is associated with complications including leakage, over filtration, or fibrosis of the surgical bleb. Morphology of the surgical bleb is an important predictor of surgical success defined as long-term IOP reduction with minimal to no complications. There have been many, often subtle, variations in the surgical technique in hopes of improving long-term IOP reduction. However, fewer changes have been implemented specifically to modify bleb morphology. In our surgical practice, we began performing a thorough dissection and advancement of Tenon's layer with incorporation into the conjunctival closure in a 2-layered manner. This technique allowed flow of aqueous to a delineated potential space between sclera and Tenon's layer. Our clinical observations were improved bleb morphology characterized by diffuse, low-lying blebs with nonischemic overlying conjunctiva compared with those performed with a more traditional trabeculectomy technique. Since we incorporated this change into our practice at a defined time, we have a small number of patients in our practice that had a more traditional trabeculectomy technique in the fellow eye. Therefore, in our surgical practice, a small number of patients had trabeculectomy in 1 eye before implementation of this new technique, and then had trabeculectomy in the fellow eye after this technique was adopted, providing opportunity for comparison of bleb morphology with and without Tenon advancement. In series we present two representative, index cases and describe our surgical technique.

The Norwich trabeculectomy study: risk factor analysis for the development of adverse, thin cystic blebs

PURPOSE

To investigate potential risk factors, particularly antimetabolite choice, with regard to the development of adverse bleb morphology in eyes that had undergone trabeculectomy surgery.

METHODS

A single-centre, observational cohort study of 631 consecutive eyes, which had undergone trabeculectomy over an 11-year period. For each case, bleb morphology was recorded at 2 years, and its association with the per-operative antimetabolite as well as potential confounding risk factors was analysed using univariate (unadjusted) and multivariate (adjusted) logistical regression analyses to identify those that could contribute to the development of adverse blebs. A standard protocol for 5-fluorouracil and mitomycin-C utilization was employed in the majority of cases.

RESULTS

When 5-fluorouracil was used (n = 257), 24% of patients formed cystic or partially cystic blebs, whereas with mitomycin-C (n = 299), only 12% formed such adverse blebs, the difference being statistically significant (OR = 3.54, p = 0.002 unadjusted; OR = 7.49, p = 0.00 adjusted). Of the other potential confounding factors, care within the private sector (OR = 0.30 p = 0.02) and a history of previous ocular surgery involving a conjunctival incision were identified as potential risk factors for the formation of adverse cystic blebs (OR = 0.28, p = 0.02).

CONCLUSIONS

Modern use of mitomycin-C appeared to be better than 5-fluorouracil as an adjunctive antimetabolite used at the time of trabeculectomy, with respect to the development of preferable final bleb morphology. The only potential preoperative risk factors found to be significant with respect to adverse cystic bleb development were care in the private health sector and previous ocular surgery involving a conjunctival incision.

Clinical profile and long term outcomes of eyes with choroidal detachment following trabeculectomy

Purpose:

To assess the long-term outcomes of choroidal detachments (CDs) in eyes following trabeculectomy.

Methods:

Retrospective comparative case series. Data of patients with CDs following trabeculectomy (5-year period) with or without cataract surgery with a minimum of 3 months of follow-up were included.

Results:

In total, 45 patients with CDs following trabeculectomy were included. The mean age was 63.27 ± 8.68 years, (M:F = 2:1); 29 of 45 eyes (64.4%) had a baseline IOP of >24 mm Hg. Patients had a median follow-up of 22.2 (IQR: 16.2–30.5) months. Further, 10 of 45 eyes (22.2%) had CDs following suture lysis. The median onset of choroidal detachment from the time of surgery was 16.0 (IQR: 11–36) days. The mean BCVA improved from 0.62 ± 0.28 to 0.24 ± 0.27 (P < 0.001) and mean IOP increased from 4.07 ± 2.66 to 11.20 ± 5.31 (P < 0.001) at last visit. The cumulative success rates were 76.4% (95% CI: 48.4–90.5) in POAG eyes and 79.3% (95% CI: 62.8–89.1) in PACG eyes (P = 0.547). Medical management was the mainstay in all patients. Four of 45 (8.88%) patients underwent subsequent choroidal drainage.

Conclusion:

Choroidal detachment following modern-day trabeculectomy has favorable long-term visual acuity and IOP outcomes. There was no difference in the long-term surgical success of trabeculectomy with choroidal detachments in primary angle-closure and open-angle glaucoma eyes. Long-term follow-up is essential to prevent chronic hypotony and trabeculectomy failure.

PRESERFLO™ MicroShunt versus trabeculectomy: first results on efficacy and safety

PURPOSE

To report efficacy and safety outcomes of the PRESERFLO™ MicroShunt compared with trabeculectomy, the current gold-standard treatment for advanced glaucoma, in the early and intermediate postoperative period.

METHODS

Institutional prospective interventional cohort study of primary open-angle glaucoma (POAG) patients scheduled for the PRESERFLO™ MicroShunt. The comparison group were POAG patients who had had received trabeculectomy and were matched for age, known duration of disease, number and classes of intraocular pressure (IOP)-lowering medications to ensure a similar conjunctival condition. The study is part of the Dresden Glaucoma and Treatment Study (DGTS), was not randomized, but used a uniform study design, with the same inclusion and exclusion criteria as well as standardized definitions of success and failure.

MAIN OUTCOME MEASURES

mean diurnal IOP (mdIOP, mean of 6 measurements), diurnal peak IOP, diurnal IOP fluctuations, glaucoma medical therapy, success rates, visual acuity, visual fields, surgical complications and interventions, and severe adverse events.

RESULTS

Fifty-two eyes of 52 patients, 26 in each group, were analysed. At 6 months, median [Q25, Q75] mdIOP was 10.8 [9.5-12.2] mmHg in the microshunt and 10.3 [7.6-11.8] mmHg in the trabeculectomy group. Reduction in mdIOP (p = 0.458), peak diurnal IOP (p = 0.539), and median diurnal fluctuation (p = 0.693) was not statistically significantly different between groups. The rate of interventions was statistically significantly higher in the trabeculectomy compared with the microshunt group (p = 0.004). None of the patients experienced severe adverse events.

CONCLUSION

Both procedures are equally effective and safe in lowering mdIOP in patients with POAG. Because the microshunt is less invasive with less follow-up and interventions needed postoperatively, it might be recommended earlier in the treatment of glaucoma.

Corneal endothelial cell density loss following glaucoma surgery alone or in combination with cataract surgery: A systematic review and meta-analysis

TOPIC

Corneal endothelial cell density (ECD) loss following glaucoma surgery with or without cataract surgery.

CLINICAL RELEVANCE

Corneal ECD loss may occur due to intraoperative surgical trauma in glaucoma surgery or postoperatively with chronic endothelial cell trauma or irritation.

METHODS

Trabeculectomy, glaucoma filtration surgery or microinvasive glaucoma surgery in participants with ocular hypertension, primary and secondary open angle glaucoma, normal tension glaucoma and angle-closure glaucoma were included. Pediatric populations and participants with pre-existing corneal disease were excluded. Laser treatments and peripheral iridotomy were excluded. Electronic databases searched in December 2021 included MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials (CENTRAL), ClinicalTrials.gov and The International Prospective Register of Systematic Reviews (PROSPERO), FDA PMA and FDA 510(k).

RESULTS

39 studies were included in quantitative synthesis. 12 months following suprachoroidal MIGS mean ECD loss was 282 cells/mm² (95% Confidence Interval (CI) 220 to 345; p <0.00001; Chi² = 0.06; I² = 0%; 2 studies; very low certainty). Mean ECD loss after Schlemm's canal implantable devices was 338 cells/mm² (95% CI 185 to 491; p<0.0001; Chi² = 0.08; I² = 0%; 2 studies; low certainty) at 12 months. When compared to phacoemulsification alone, Schlemm's canal implants combined with phacoemulsification showed statistically significant mean ECD reduction at 24 months; mean difference of ECD was -19% (95% CI -37% to -2%; p=0.03; Chi² = 3.04; I² = 34%; 3 studies; low certainty). Mean ECD loss was 64 cells/mm² (95% CI 21 to 107; p=0.004; Chi² = 4.55; I² = 0%; 6 studies; low certainty) following Schlemm's canal procedures (without implantable devices) at 12 months. At 12 months the mean ECD loss after trabeculectomy was 33 cells/mm² (95% CI -38 to 105, p=0.36, Chi² = 1.17; I² = 0%; moderate certainty). At 12 months mean ECD loss was 121 cells/mm² (95% CI 53 to 189; p=0.0005; Chi² = 3.00; I² = 0%; 5 studies; low certainty) after Express implantation. When compared to control fellow eye, aqueous shunt surgery reduced ECD by 5.75% (95% CI -0.93 to 12.43; p=0.09 Chi² = 1.32; I² = 0%; low certainty) and 8.11% ECD loss (95%CI 0.06 to 16.16 p=0.05; Chi²= 1.93; I²=48%) at 12 and 24 months, respectively.

CONCLUSIONS

Overall there is low certainty evidence to suggest that glaucoma surgery involving long-term implants has a greater extent of ECD loss than glaucoma filtration surgeries without the use of implants. The results of this review support long-term follow-up (beyond 36 months) to assess ECD loss and corneal decompensation following implantation of glaucoma drainage implants.

Comparison of Surgical Outcomes between Trabeculectomy with Mitomycin C and Ahmed Valve Implantation with Mitomycin C in Eyes with Uveitic Glaucoma

We compared 1-year outcomes of trabeculectomy with mitomycin C (MMC) and Ahmed valve implantation with MMC as a first surgical procedure in patients with uveitic glaucoma. A total 38 eyes of 38 patients undergoing trabeculectomy (n =16) or Ahmed valve implantation (n = 22) were included. Surgical success was defined as intraocular pressure (IOP) ≤21 mmHg, IOP reduction ≥20% from baseline, no secondary glaucoma surgery, and no loss of light perception. The main outcome measurements including success rate, IOP, and the number of antiglaucoma medications and complications were compared. The overall success rates were comparable between the Ahmed and trabeculectomy groups (81.3 vs. 81.8%, p = 0.987). The mean IOPs were similar as well (p = 0.084), though the number of antiglaucoma medications was significantly lower in the trabeculectomy group than in the Ahmed group (1.0 ± 1.2 vs. 2.2 ± 1.1; p = 0.005). A statistically significant reduction in corneal endothelial cell density was noted in the Ahmed group (p = 0.004). Both treatments offered reasonable IOP control and safety for eyes with uveitic glaucoma. However, significantly fewer antiglaucoma medications were used in the trabeculectomy group. Furthermore, our results suggest that cautious postoperative monitoring with regard to corneal endothelial cell density should be additionally performed after Ahmed valve implantation.

The long-term postoperative effect of the Baerveldt glaucoma drainage device and of a trabeculectomy on the corneal endothelium

PURPOSE

To determine whether the postoperative corneal endothelial cell density (ECD) differs between glaucoma patients who underwent Baerveldt implant (BGI) surgery and patients who underwent a trabeculectomy (TE) over 5 years ago.

METHODS

Cross-sectional, observational study including 34 patients who underwent TE and 36 patients who underwent BGI surgery 5-11 years ago, as part of a randomized clinical trial. None of the patients had a history of intraocular surgery prior to their glaucoma surgery. Central and peripheral ECD was measured by using a non-contact specular microscope.

RESULTS

Central and peripheral ECD in the TE group was 2285 ± 371 cells/mm² (mean ± SD) and 2463 ± 476 cells/mm² , respectively. Central and peripheral ECD in the BGI group was 1813 ± 745 cells/mm² and 1876 ± 764 cells/mm² , respectively. The central and peripheral ECD was statistically significantly higher in the TE group than in the BGI group (p = 0.001 for both). Additional intraocular surgical interventions were more prevalent in the BGI group (23) than in the TE group (5) (p < 0.001). In a subanalysis, without eyes that had undergone additional surgical interventions, only the peripheral ECD was statistically significantly higher in the TE group compared with the BGI group (p = 0.011). For the BGI group, a longer postoperative period resulted in a lower central ECD (r = -0.614, p = 0.004).

CONCLUSION

Long-term ECD in eyes that underwent a BGI was considerably lower compared with eyes that underwent a TE, mainly in the peripheral cornea. This suggests that BGI causes a larger decrease of ECD than TE. Additionally, the decrease after BGI appears to continue for a longer period than after TE.

The surgical management of glaucoma: A review

After a long period of little change, glaucoma surgery has experienced a dramatic rise in the number of possible procedures in the last two decades. Glaucoma filtering surgeries with mitomycin C and glaucoma drainage devices remain the standard of surgical care. Other newer surgeries, some of which are minimally or microinvasive glaucoma surgeries, target existing trabecular outflow, enhance suprachoroidal outflow, create subconjunctival blebs, or reduce aqueous production. Some require the implantation of a device such as the iStent, Hydrus, Ex-PRESS, XEN and PRESERFLO, whilst others do not-Trabectome, Kahook dual blade, Ab interno canaloplasty, gonioscopy-assisted transluminal trabeculotomy, OMNI and excimer laser trabeculotomy. Others are a less destructive variation of an established procedure, such as micropulse transscleral cyclophotocoagulation, endoscopic cyclophotocoagulation and ultrasound cycloplasty. Cataract surgery alone can be a significant glaucoma operation. These older and newer glaucoma surgeries, their mechanism of action, efficacy and complications are the subject of this review.

Inter-Eye Comparison of the Ocular Surface of Glaucoma Patients Receiving Surgical and Medical Treatments

Background: Ocular surface frequently affects glaucoma patients. In this paper we aimed at evaluating the impact of glaucoma surgery on the ocular surface of patients who received unilateral trabeculectomy. Methods: 26 consecutive patients successfully treated with trabeculectomy on one eye (Trab Eye) and under control with topical treatments on the fellow eye (Med Eye) were included in this observational study. They received IDEEL and OSDI questionnaires, Tear Film Osmolarity (TFO), grading of conjunctival hyperemia, fluorescein tear break-up time (tBUT), grading of corneal staining and Schirmer test. Results: IDEEL and OSDI scores were 48 ± 38 and 11 ± 12, respectively, with moderate correlation (r = 0.50, p = 0.03). Compared with Med eyes, Trab Eyes had higher tBUT (6.5 ± 3.5 vs. 5.1 ± 2.7 s, p = 0.004), lower conjunctival hyperemia (0.8 ± 0.9 and 1.7 ± 1.1 respectively, p < 0.001) and lower corneal staining (0.3 ± 0.5 and 0.6 ± 0.5, respectively, p = 0.03). Correlation between corneal staining and conjunctival hyperemia was 0.55 in Trab Eyes (p = 0.01) and 0.44 in Med Eyes (p > 0.05). Patients with bilateral corneal staining had had threefold worse questionnaire scores (p < 0.05). The duration of treatment and the daily exposure to preservatives did not directly affect OS parameters in this cohort of patients. Conclusions: Patients receiving successful trabeculectomy showed better OS homeostasis (higher TBUT, lower grading of conjunctival hyperemia and corneal staining) than fellow medically treated eyes. Presence of corneal epithelial damage in both eyes is the factor more consistently affecting questionnaire scores.

Management of Childhood Glaucoma Following Cataract Surgery

Glaucoma remains a frequent serious complication following cataract surgery in children. The optimal approach to management for 'glaucoma following cataract surgery' (GFCS), one of the paediatric glaucoma subtypes, is an ongoing debate. This review evaluates the various management options available and aims to propose a clinical management strategy for GFCS cases. A literature search was conducted in four large databases (Cochrane, PubMed, Embase, and Web of Science), from 1995 up to December 2021. Thirty-nine studies-presenting (1) eyes with GFCS; a disease entity as defined by the Childhood Glaucoma Research Network Classification, (2) data on treatment outcomes, and (3) follow-up data of at least 6 months-were included. Included papers report on GFCS treated with angle surgery, trabeculectomy, glaucoma drainage device implantation (GDD), and cyclodestructive procedures. Medical therapy is the first-line treatment in GFCS, possibly to bridge time to surgery. Multiple surgical procedures are often required to adequately control GFCS. Angle surgery (360 degree) may be considered before proceeding to GDD implantation, since this technique offers good results and is less invasive. Literature suggests that GDD implantation gives the best chance for long-term IOP control in childhood GFCS and some studies put this technique forward as a good choice for primary surgery. Cyclodestruction seems to be effective in some cases with uncontrolled IOP. Trabeculectomy should be avoided, especially in children under the age of one year and children that are left aphakic. The authors provide a flowchart to guide the management of individual GFCS cases.

Different surgical modalities for management of uveitic glaucoma: 2 year comparative study

PURPOSE

The aim of this study was to compare outcome of 3 different surgical modalities for management of uveitic glaucoma (UG).

METHODS

This is a prospective comparative study, carried out on a cohort of 105 eyes (105 patients) with UG of different aetiologies. Patients were randomly allocated to group A (trabeculectomy), group B (Ahmed glaucoma valve; AGV) or group C (Trans-scleral diode laser cyclophotocoagulation, TDLC). Postoperatively, all patients were followed up for 2 years. Humphrey SITA standard perimetry was done 6, 12 and 24 months. Complete success was defined as IOP ≤ 21 mmHg and relative decrease of ≥20%, without additional glaucoma surgery or antiglaucoma medication, qualified success as IOP ≤ 21 mmHg and additional reduction of ≥20% in IOP, without additional glaucoma surgery, but with topical medications, while failure was considered when IOP was not controlled with topical medications and the patient needed additional surgery, or hypotony for ≥2 months.

RESULTS

At first, IOP was significantly lower with AGV and significantly higher with TDLC, with significant drop and percentage drop between the three groups. Starting from the 6th month postoperatively till the end of the 2-year period, there was no statistically significant difference between the 3 groups. There was no significant difference between the three groups, with complete success achieved in 60% with trabeculectomy, 68.6% with AGV and 62.9% with TDLC. There was significant difference for inflammatory cells grading; 65.7% of eyes with trabeculectomy had 2+ cells, 57% with AGV had 0 cells while 45.7% with TDLC had 1+ cells.

CONCLUSION

The three surgical modalities had the same IOP-lowering effect on the long run, with complete success rate that is close enough between them, with AGV revealing the least inflammation, which might be the cause of more stable VF with Ahmed's valve proving its superiority to the other 2 techniques for inflammatory glaucoma.

Updates on the utility of anterior segment optical coherence tomography in the assessment of filtration blebs after glaucoma surgery

The formation of filtration blebs is the main drainage mechanism for reducing intraocular pressure after traditional incisional glaucoma surgery such as trabeculectomy and non-penetrating deep sclerotomy. Early and short-lasting blebs may also occur after canaloplasty. Bleb formation also plays an important role after the implantation of glaucoma drainage devices, including Minimally Invasive Glaucoma Surgery devices. Anterior segment optical coherence tomography (AS-OCT) is a rapid and non-invasive high-resolution imaging technique that has evolved in recent years to become a routine examination. Anterior segment optical coherence tomography (AS-OCT) provides key information in the assessment and follow-up of glaucoma surgery, especially in the assessment of filtration blebs. Thus, bleb morphology can be qualitatively classified into diffuse, cystic, encapsulated and flattened, and AS-OCT imaging can also provide several quantitative parameters of the bleb, such as total bleb height, bleb fluid-filled cavity height, bleb wall thickness, number of microcysts and trabeculectomy opening size. These parameters could have an impact on clinical management during follow-up because they may predict the success or failure of the surgery in the early and late postoperative periods. Additionally, they may also guide the procedures used to increase filtration and reduce intraocular pressure, such as bleb needling and laser suture lysis.

Outcomes and risk factors for failure of trabeculectomy with mitomycin C in children with traumatic glaucoma - A retrospective study

Purpose:

To determine surgical outcomes and risk factors for failure of trabeculectomy with mitomycin C (TMMC) in pediatric traumatic glaucoma.

Methods:

Children who underwent TMMC post trauma from January 2014 to December 2019 were reviewed. Demographic features, ocular findings, and surgery details were noted. Surgical success was defined as achieving intraocular pressure (IOP) within 6–21 mm Hg.

Results:

Seventy-one eyes of seventy patients underwent TMMC. The mean age of the patients was 11.28 ± 3.63 years with a male/female ratio of 13:1. The median time from trauma to IOP rise was 13 days. The majority of the patients (n = 64, 90.1%) had close globe injury. Baseline IOP was 39.3 ± 10.5 mm Hg. Results of the surgery were noted at the last visit. Cumulative success was noted in 51 (71.8%) eyes, while 20 (28.2%) eyes were labeled failures. Mean IOP reduced from 39.3 ± 10.5 to 14.5 ± 8.1 mm Hg. Mean visual acuity improved from 2.3 ± 0.93 to 1.19 ± 1.08 logMAR. Post surgery, the mean follow-up of the patients was 20.3 ± 11.4 months. Age <6 years (RR 3.6), elevated IOP at 1 month after TMMC (RR 2.19), and hypotony within a week of surgery (RR 1.81) were found as independent risk factors of surgical failure.

Conclusion:

TMMC is effective in reducing IOP in traumatic glaucoma. Young age and inability to control IOP within normal ranges in the immediate period after surgery are important risk factors of failure.