Secondary intervention after failed initial intervention for primary congenital glaucoma

AIM

To report on the outcome of subsequent interventions after failed initial intervention for primary congenital glaucoma (PCG).

METHODS

Retrospective chart review of children presenting with PCG and failed the initial glaucoma surgery in Alexandria Main University Hospital from 2005 to 2017. The data included demographics, preoperative, operative and postoperative clinical characteristics. Success was defined as IOP<16mmHg and <20% from the presenting IOP and C/D ratio like or better than presentation.

RESULTS

The charts of 531 (260 right, 49%) eyes of 360 (224 males, 62%) children presenting with PCG and failed the initial glaucoma surgery (58 [31 right, 53%] eyes [10.9%] of 50 [28 males, 56%] children) revealed that at initial presentation, the mean±standard deviation (range, median) of the age of the children subjected to one successful glaucoma procedure and the study children was 8.6±11.7 (0.6-109, 5.2) and 4.9±6.1 (0.5-34.4, 3.0) months, respectively. Each of the study eyes was subjected to 2.6±0.8 (2-5.2) glaucoma procedures. The mean±standard deviation (range, median) duration between the initial and second glaucoma surgery and the duration of follow-up was 6.9±7.8 (0.7-39,3.9) and 61.5±32.1 (12.0-139.1, 60.1) months, respectively. At the final follow-up visit success was reported in 41 (70.1%) eyes by IOP<16mmHg criterion, 39 (67.2%) eyes by IOP>20% reduction criterion and in 28 (out of 35 eyes, 80.0%) by the optic nerve condition (C/D ratio) criterion. Success by all 3 criteria was reported in 25 (out of 35 eyes, 71%) eyes.

CONCLUSIONS

A repeat glaucoma surgical procedure maybe needed in up to 11% of operated PCG eyes, with the subsequent glaucoma surgical procedures being successful by about 70%.

Efficacy of anti-vascular endothelial growth factor and mitomycin C on wound healing after trabeculectomy in glaucoma patients: A meta-analysis

Trabeculectomy is the main surgical treatment for glaucoma, but scar formation during wound healing may lead to surgical failure. In this study, we evaluated the efficacy of anti-vascular endothelial growth factor (anti-VEGF) and mitomycin C (MMC) on wound healing after glaucoma surgery. We have been looking for Pubmed, Embase and other databases. The last time we looked at an electronic database was August 2023. A case control study was conducted to compare the use of anti-VEGF and mitomycin C for the treatment of glaucoma. We used the Cochrane standard methodology for collecting and analysing the data. Based on the criteria of inclusion, we have determined 369 related papers and selected seven eligible trials for data analysis. Three hundred and twenty-six cases were treated with trabeculectomy, of which 166 were injected with anti-VEGF and 160 were given MMC for trabeculectomy. In six trials, anti-VEGF and MMC were not found to have any statistical significance on postoperative wound leakage after surgery (OR, 1.55; 95% CI, 0.71, 3.35 p = 0.27). The three trials showed that anti-VEGF and MMC did not differ in terms of reducing postoperative wound hypotony after surgery (OR, 0.78; 95% CI, 0.20, 3.11 p = 0.73). Five trials demonstrated that anti-VEGF and MMC were not associated with a lower incidence of shallow anterior chamber (OR, 1.17; 95% CI, 0.5, 2.76 p = 0.71). There is no significant difference in the effect of anti-VEGF and MMC on wound healing after glaucoma surgery. A multicentre randomized controlled trial with a larger sample size is needed to confirm this study.

PRESERFLO MicroShunt in Severe Myopia: A Case Report and Review of the Literature

The PRESERFLO™ MicroShunt (MP; Santen Inc., Osaka, Japan) is a minimally invasive bleb surgery (MIBS) manufactured to treat primary open-angle glaucoma (POAG), with lower postoperative adverse effects than with conventional filtering surgeries. We describe here the case study of a 58-year-old woman who presented with bilateral severe myopia with bilateral advanced POAG and unreached target pressure under quadritherapy, who was successfully managed by PM surgery. A review of the literature completes our observation. At presentation, the patient had a spherical equivalent of - 7.50 RE and - 7.75 LE with an IOP of 22 mmHg right and left eye (RLE) under quadritherapy, and with severe bilateral visual field loss, including scotomas within the central 5°. The patient presented with systemic hypertension treated with an antihypertensive drug. Two selective laser trabeculoplasties (SLT), performed 3 months apart, were first tried on the LE, without any change in IOP at 2 months. After considering the high risk of postoperative complications, a PM operation was proposed, with a targeted IOP in the mid-fifteens RLE. The patient's eyes underwent PM surgery with mitomycin C (MMC) MMC0.2 mg/mL for 3 minutes without any complications. The LE required 2 consecutive needlings with 1 mL MMC0.2 mg/mL. At 24 months after surgery, the two eyes gave successful results without the need for any additional medical therapy, and with well-functioning conjunctival blebs. The PM was an effective alternative to the gold standard trabeculectomy in our severely myopic patient. A comparative study between conventional filtering operations and this MIBS in highly myopic patients would confirm our observation.

Evaluating the effect of pulse energy on femtosecond laser trabeculotomy (FLT) outflow channels for glaucoma treatment in human cadaver eyes

BACKGROUND AND OBJECTIVES

Femtosecond laser trabeculotomy (FLT) creates aqueous humor outflow channels through the trabecular meshwork (TM) and is an emerging noninvasive treatment for open-angle glaucoma. The purpose of this study is to investigate the effect of pulse energy on outflow channel creation during FLT.

MATERIALS AND METHODS

An FLT laser (ViaLase Inc.) was used to create outflow channels through the TM (500 μm wide by 200 μm high) in human cadaver eyes using pulse energies of 10, 15, and 20 μJ. Following treatment, tissues were fixed in 4% paraformaldehyde. The channels were imaged using optical coherence tomography (OCT) and assessed as full thickness, partial thickness, or not observable.

RESULTS

Pulse energies of 15 and 20 μJ had a 100% success rate in creating full-thickness FLT channels as imaged by OCT. A pulse energy of 10 μJ resulted in no channels (n = 6), a partial-thickness channel (n = 2), and a full-thickness FLT channel (n = 2). There was a statistically significant difference in cutting widths between the 10 and 15 μJ groups (p < 0.0001), as well as between the 10 and 20 μJ groups (p < 0.0001). However, there was no statistically significant difference between the 15 and 20 μJ groups (p = 0.416).

CONCLUSIONS

Fifteen microjoules is an adequate pulse energy to reliably create aqueous humor outflow channels during FLT in human cadaver eyes. OCT is a valuable tool when evaluating FLT.

A comparative study of cystoid macula edema following glaucoma drainage device surgery versus trabeculectomy

PURPOSE

To assess and compare the risk for development of cystoid macula edema (CME) after glaucoma drainage device (GDD) implantation versus conventional trabeculectomy with mitomycin (trab) for glaucoma.

METHODS

Retrospective review of consecutive patients receiving trab or GDD implantation between 2016 and 2018. Inclusion criteria were availability of pre- and postoperative spectral domain optical coherence tomography (SD-OCT) of the macula. SD-OCT images were evaluated for presence of CME qualitatively, central subfield thickness (CST) and macular volume (MV).

RESULTS

73 eyes could be included, 42 received trab and 31 GDD surgery. Eyes receiving trab on average had 0.8 ± 0.8 previous intraocular operations, while eyes with GDD implantation had 3.1 ± 1.9 (p < 0.001). Occurrence of postoperative CME was significantly more frequent after GDD implantation (6 out of 31 (19.4%)) than after trab (2 out of 42 eyes = 4.8%), (p = 0.049). Mean preoperative CST as well as MV was comparable in both groups (CST before trab: 282.7 ± 23.0 µm, CST before GDD 284.2 ± 27.3 µm, p = 0.287; MV before trab: 7.8 ± 1.1 mm3, MV before GDD: 8.0 ± 0.8mm3, p = 0.305). Mean postoperative CST and MV were significantly higher after GDD (CST 338.5 ± 129.3 µm, MV 8.8 ± 2.6 mm3) than after trabeculectomy (CST 290.6 ± 60.2 µm, p = 0.038; MV 7.8 ± 1.2mm3, p = 0.039).

CONCLUSIONS

In real-life conditions, GDD surgery seems to be associated with a higher risk to develop CME when compared to conventional trabeculectomy. This information may be helpful for glaucoma surgeons to advise the patients on postoperative risks of surgery.

Phacoemulsification with gonioscopy-assisted transluminal trabeculotomy versus phacoemulsification alone in primary angle closure glaucoma: A randomized controlled study

PURPOSE

To assess the safety and efficacy of combining phacoemulsification with gonioscopy-assisted transluminal trabeculotomy (GATT) compared to phacoemulsification alone in the management of primary angle closure glaucoma (PACG).

METHODS

Prospective, institutional study in which eyes requiring surgery for PACG were randomized to undergo phacoemulsification followed by GATT (phaco-GATT group) or phacoemulsification alone. Success was defined as having a final IOP of 6-20 mmHg with no subsequent glaucoma surgery or vision-threatening complications.

RESULTS

Thirty-six eyes underwent phaco-GATT with 360° angle incision and 38 eyes underwent phacoemulsification alone. IOP and glaucoma medications were significantly lower in the phaco-GATT group at 1, 3, 6, 9 and 12 months. The success rate in the phaco-GATT group was 94.4% after 12.16 ± 2.03 months, with 75% of eyes being off medications compared to 86.8% after 12.47 ± 4.27 months in the phaco group, with 42.1% off medications. (p = 0.008). Hyphema and fibrinous anterior chamber reaction were the most common complications in the phaco-GATT group and resolved with conservative treatment or required YAG capsulotomy. Although this delayed visual rehabilitation in the phaco-GATT group, it did not affect the final visual outcome with no significant difference in the final best-corrected visual acuity between both groups (p = 0.25).

CONCLUSION

Combining phacoemulsification with GATT in PACG yielded more favourable outcomes in terms of IOP, glaucoma medications and surgical success. Although the postoperative hyphema and fibrinous reaction may delay visual rehabilitation, GATT further lowers the IOP by breaking residual peripheral anterior synechiae and removing the dysfunctional trabeculum circumferentially, while avoiding the risks inherent in more invasive filtering procedures.

Wound modulation in glaucoma surgery: The role of anti-scarring agents

Filtration surgery is one of the most frequently performed surgeries in the management of glaucoma, and trabeculectomy is considered the gold standard surgical technique for the same. Though trabeculectomy has been reported to have an excellent initial success rate, about 30% of them fail in 3 years, and nearly 50% of them fail in 5 years. The most significant risk of failure still seems to be wound scarring, especially episcleral fibrosis, leading to bleb failure. As a result, it is essential to explore the role of anti-scarring agents, including mitomycin C, and 5-fluorouracil in wound modulation and improving the bleb survival rate. Since these agents are widely used in trabeculectomy, it is crucial to understand the various modes of application, advantages, and adverse effects of these agents. On an evidence-based approach, all these points have been highlighted in this review article. In addition, the newer agents available for wound modulation and their scope for practical application are discussed.

Indocyanine green-assisted goniotomy in eyes with hazy cornea

Corneal haze, due to edema or opacity, is a major contraindication for performing ab interno angle surgeries such as goniotomy in children with primary congenital glaucoma (PCG), despite otherwise favorable surgical outcomes expected in these patients. In this case series involving patients of PCG with moderate corneal haze, the authors describe a technique for performing goniotomy in cases with compromised visibility by using indocyanine green (ICG) to aid in the visualization of angle structures. The authors used 0.2% ICG intracamerally, which stained the anterior and posterior trabecular meshwork (TM) with different intensities, before proceeding with goniotomy. The junction between the two zones was discernible due to the contrast imparted by ICG staining, despite poor visibility, allowing the surgeon to incise the TM at the correct site. The possibility of performing goniotomy in such patients with the help of ICG can revolutionize our surgical approach to patients with PCG and corneal edema.

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.

Comparison of the safety and efficacy of Mitomycin C 0.02% used intra-operatively by subconjunctival injection versus direct scleral application using sponges in phacotrabeculectomy: A prospective randomized controlled trial

PURPOSE

To compare the safety and efficacy of subconjunctival injection (MMC: 0.02%) to those with subconjunctival application of sponges soaked in Mitomycin C (MMC: 0.02%) intra-operatively in patients who underwent phacotrabeculectomy.

METHODS

A total of 68 patients undergoing phacotrabeculectomy were randomized into two groups; the sponge group received 0.02% MMC-soaked sponges (n = 38), and the injection group received subconjunctival injection of 0.02% MMC (n = 30). The primary outcome was post-operative mean intra-ocular pressure reduction (IOP). The secondary outcomes were bleb morphology using Indiana Bleb Appearance Grading Score (IBAGS) and anterior segment optical coherence tomography (AS-OCT), post-operative use of 5-fluorouracil, and complications rates. These were compared at 1 week and 1, 3, and 6 months post-operatively. Complete success was defined as ≥30% reduction in IOP without anti-glaucoma medications.

RESULTS

In sponge and injection groups, the mean pre-operative IOP was 29.1 ± 8.1 and 29.8 ± 8.8 mmHg, respectively. At 6 months, IOP in sponge and injection groups reduced by 52% (14 ± 3.6 mmHg, P < 0.001) and 50% (15.2 ± 4.1 mmHg, P < 0.001), respectively. Complete success was observed in 90.9% in the sponge group and 95.83% in the injection group. Both groups had diffuse, shallow, relatively avascular blebs at 6 months using IBAGS and AS-OCT. A few complications were seen in the sponge group during this period, which were not vision-threatening.

CONCLUSION

Subconjunctival MMC injection is an effective, safe, convenient, and time-saving alternative to sponge-soaked delivery of MMC in phacotrabeculectomy.

Histopathologic correlates of trabecular meshwork in microincisional trabeculectomy

PURPOSE

To report the histopathologic correlates of trabecular meshwork (TM) specimens procured by microincisional trabeculectomy (MIT) for different severities of glaucoma (early glaucoma: visual field mean deviation [MD] <-6 dB, moderate glaucoma: MD from - 6 to - 12 dB, and advanced glaucoma: MD <-12 dB).

METHODS

TM specimens from four patients undergoing MIT with or without cataract surgery were analyzed by routine histopathology for structural changes. The number of cells, the number of cells with spindle-shaped nuclei suggestive of epithelial-mesenchymal transformation (EMT), and the distance between the trabecular beams were calculated using different tools on freely available ImageJ software using the line or pint/count tool.

RESULTS

The TM specimens procured from two early and two advanced glaucoma cases showed decreasing cellularity and decreased compact arrangement of the trabecular beams in severe disease stages. The number of cells and preserved architecture in all four specimens were evident, with > 50 cells being present per section in all four cases despite the glaucoma being of advanced disease stage in two patients.

CONCLUSION

The TM specimens obtained from MIT can be utilized for downstream analysis using different molecular methods for studying the molecular events in the tissue from early to severe glaucoma.

Quantification of Postoperative Inflammation in Laser and Surgical Procedures for Glaucoma with Laser Flare Photometry: A Review of the Literature

PURPOSE

To review the application of laser flare photometry (LFP) in the objective quantification of aqueous flare (anterior chamber inflammation) post laser and surgical procedures for glaucoma.

METHODS

A search was undertaken using the following: PubMed (all years), the Web of Science (all years), Ovid MEDLINE (R) (1980 to 30 March 2023), Ovid MEDLINE (R) Daily Update 30 March 2023, MEDLINE and MEDLINE non-indexed items, Embase (1980-2021, week 52), Ovid MEDLINE (R) and Epub Ahead of Print, in-Process & Other Non-Indexed Citations and Daily (1980 to 30 March 2023), CENTRAL (including Cochrane Eyes and Vision Trials Register), metaRegister of Controlled Trials (mRCT) (www.controlled-trials.com), ClinicalTrials.gov (www.clinicaltrial.gov) and the World Health Organization (WHO) International Clinical Trials Registry Platform (www.who.int/ictrp/search/en). Search terms included "aqueous flare," "anterior chamber inflammation," "tyndallometry," "laser flare photometry" combined with "laser," "iridotomy," "trabeculoplasty," "cataract surgery," "phacoemulsification," "glaucoma surgery," "minimally invasive glaucoma surgery," "trabeculectomy," "aqueous shunt," "glaucoma drainage" and "cyclophotocoagulation."

RESULTS

The majority of studies utilizing laser flare photometry in grading flare have been post laser trabeculoplasty. The degree of flare produced varies according to the type of glaucoma laser or surgery performed, with filtration procedures and glaucoma drainage devices having marked and prolonged detectable levels. Aqueous flare in cyclodestructive procedures positively correlated with intraocular pressure (IOP) reduction.

CONCLUSION

In comparison to clinician grading, laser flare photometry provides a more objective measure of post-surgical inflammation in eyes that have undergone laser and surgery for glaucoma. Further research is warranted into how this instrument can be utilized to identify eyes at high risk of failure and other adverse outcomes after glaucoma surgery.

Ab-Externo MicroShunt versus Trabeculectomy in Primary Open-Angle Glaucoma: Two-Year Results from a Randomized, Multicenter Study

PURPOSE

To compare the effectiveness and safety of the MicroShunt (Santen Inc) versus trabeculectomy in patients with primary open-angle glaucoma (POAG).

DESIGN

Prospective, randomized, multicenter trial conducted in the United States and Europe.

PARTICIPANTS

Adult patients (aged 40-85 years) with mild to severe POAG inadequately controlled on maximum tolerated medical therapy and intraocular pressure (IOP) ≥ 15 mmHg and ≤ 40 mmHg.

METHODS

Patients were randomized 3:1 to stand-alone MicroShunt implantation (n = 395) or trabeculectomy (n = 132), both augmented with mitomycin C (MMC) 0.2 mg/ml for 2 minutes.

MAIN OUTCOME MEASURES

The primary effectiveness end point was surgical success, defined as ≥ 20% reduction in mean diurnal IOP from baseline with no increase in glaucoma medications. Secondary end points included changes in mean IOP and medication use from baseline and the need for postoperative interventions.

RESULTS

At 2 years, the rate of surgical success was lower in the MicroShunt group than in the trabeculectomy group (50.6% vs. 64.4%, P = 0.005). Mean diurnal IOP was reduced from 21.1 ± 4.9 mmHg at baseline to 13.9 ± 3.9 mmHg at 24 months in the MicroShunt group and from 21.1 ± 5.0 mmHg at baseline to 10.7 ± 3.7 mmHg at 24 months in the trabeculectomy group (P < 0.001 compared with baseline in both groups). Mean medication use decreased from 3.1 to 0.9 in the MicroShunt group and from 2.9 to 0.4 in the trabeculectomy group (P < 0.001 compared with baseline in both groups). Adverse events at 2 years were generally similar in the 2 groups, except that hypotony was more common in eyes undergoing trabeculectomy (51.1% vs. 30.9%, P < 0.001). Repositioning or explantation of the implant occurred in 6.8% of MicroShunt patients. The majority of these patients had device removal at the time of subsequent glaucoma surgery. Vision-threatening complications were uncommon in both groups.

CONCLUSION

At 2 years, both the MicroShunt and trabeculectomy provided significant reductions in IOP and medication use, with trabeculectomy continuing to have greater surgical success.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Early Outcomes of Combined Phacoemulsification and Ab Interno Tanito Microhook Trabeculotomy in Open-Angle Glaucoma

PURPOSE

To study the early postoperative efficacy and safety of an Ab Interno microhook trabeculotomy (microLOT) combined with cataract surgery in patients with open-angle glaucoma.

METHODS

This prospective, randomized, interventional study was conducted on consecutive patients with visually significant cataract and mild-moderate open-angle glaucoma. One hundred fourteen patients were included for analysis. The patients were randomized to undergo microhook trabeculotomy with phacoemulsification (group 1) or phacoemulsification alone (group 2). All patients were evaluated on postoperative day 1, 15, and 30, as well as 3, 6, and 12 months postoperatively. A P value < 0.05 was considered statistically significant. Baseline and follow-up visits were compared to determine significant differences in the number of antiglaucoma medications (AGMs), intraocular pressure (IOP), and best-corrected visual acuity.

RESULTS

There were 57 patients in each group. The baseline characteristics were similar between the 2 groups, except the number of AGMs, which was greater in group 2. The mean preoperative IOP for group 1 (phaco-microLOT) was 26.5 mmHg ± 5.2 and group 2 (phaco-alone group) was 25.3 mmHg ± 3.1 which decreased to 12.5 mmHg ±3.6 (P < 0.001) and 20.0 mmHg ± 2.7(P < 0.001) at 12 months, respectively. Logarithm of the minimum angle of resolution visual acuity improved from 0.48 (interquartile range [IQR], 0.30-0.60) preoperatively to 0.00 (0.00-0.18) postoperatively (P < 0001) in group 1 and improved from 0.30 (IQR, 0.30-0.48) to 0.00 (0.00-0.00) in group 2 (P < 0.001). In group 1, the mean (standard deviation [SD]) AGM used preoperatively was 0.6 (0.9) which was significantly reduced to 0.2 (0.5) at 12 months postoperatively, whereas in group 2, at 12 months, the mean (SD) AGM used was reduced from 1.4 (0.6) to 1.1 (0.9). In group 1, 90.3% of eyes achieved complete success at the end of 1 year. The most common complication was hyphema, noted in 4 patients with 1 eye requiring an anterior chamber washout.

CONCLUSION

Ab interno microhook trabeculotomy (microLOT) combined with phacoemulsification in patients with open-angle glaucoma is an efficacious procedure with relatively minimal complications.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Outcome of combined trabeculectomy with cataract surgery in patients on prostaglandin analogs and aqueous suppressants

PURPOSE

To compare the effect of prostaglandin analogs (PGA) against other glaucoma medications (non-PGA) on the intraocular pressure (IOP) outcomes of combined trabeculectomy with phacoemulsification, and the conjunctival cell profile in persons with primary open-angle (POAG) and pseudoexfoliation glaucoma (PXFG).

METHODS

A prospective cohort study was conducted among 116 patients with POAG or PXFG on glaucoma medications for a minimum of 3 months undergoing glaucoma triple procedure. Patients were divided into two groups (PGA and non-PGA) based on preoperative exposure to PGA. IOP outcomes were assessed for up to 2 years. Conjunctival biopsy specimens were obtained at the time of surgery, and histopathological analysis was performed.

RESULTS

Forty-two patients were in the PGA group, 67 were in the non-PGA group, and seven were lost to follow-up. The non-PGA group had lesser mean postoperative IOP and needed fewer postoperative medications compared to the PGA group in all visits up to 2 years. The non-PGA group had better complete success rate (50.7% vs. 14.3%, P < 0.001). Kaplan-Meier survival estimates showed a significant difference in cumulative complete success rate between non-PGA (67%) and PGA (26%) by 24 months ( P < 0.001). The Cox proportional model showed the type of drug to be significantly associated with surgical failure. Histopathological analysis revealed that the PGA group had higher numbers for each type of inflammatory cell (except mast cells) compared to the non-PGA group.

CONCLUSION

Patients on PGA are likely to have a higher postoperative IOP and may need more medications for IOP control after a glaucoma triple procedure.

Hypotony in the early postoperative period after MicroShunt implantation versus trabeculectomy: A registry study

PURPOSE

A comparison of the safety and efficacy of the MicroShunt versus trabeculectomy in the early postoperative period, with a particular focus on hypotony.

METHODS

In this registry study, we evaluated 200 eyes of 200 glaucoma patients who underwent filtration surgery at Oslo University Hospital between 2017 and 2021. Of these patients, 100 had a Preserflo MicroShunt (Santen) implantation and 100 had a trabeculectomy procedure. The patients were examined per standard hospital protocol after filtration surgery. Data were extracted from the 4- and 8-week visits. We defined hypotony as intraocular pressure (IOP) < 6 mmHg.

RESULTS

The mean preoperative IOP was 20.6 ± 7.1 mmHg in the MicroShunt group and 21.6 ± 7.1 mmHg in the trabeculectomy group, and the patients used a mean of 3.0 ± 0.9 and 3.1 ± 0.9 glaucoma medications, respectively. After 8 weeks, IOP was reduced to 10.4 ± 5.4 mmHg and 11.3 ± 4.6 mmHg, respectively (p = 0.23). During the early postoperative period, hypotony was registered in 63% of the MicroShunt patients and in 21% of the patients in the trabeculectomy group (p < 0.001); and 11% and 1%, respectively, of the patients developed choroidal detachments (p < 0.003). One patient in the MicroShunt group required reoperation due to hypotony.

CONCLUSIONS

In this registry study, we found that the Preserflo MicroShunt and trabeculectomy had equally satisfactory IOP-lowering effects during the early postoperative period. In this same period, a high number of patients in the MicroShunt group developed hypotony.

Optimal Performance of Selective Laser Trabeculoplasty: Results from the Swedish Optimal SLT Multicenter Randomized Controlled Trial

PURPOSE

Selective laser trabeculoplasty (SLT) is a first-line treatment for glaucoma and ocular hypertension. However, due to insufficient comparative evidence in efficacy and safety, several SLT treatment protocols are currently used in practice. The objective of this trial was to compare the clinical outcomes of the 4 most significant SLT variants.

DESIGN

Prospective, multicenter, masked, randomized controlled trial (RCT).

PARTICIPANTS

Four hundred patients with glaucoma or ocular hypertension. The cohort consisted of both treatment-naive patients and patients undergoing glaucoma treatment, at different stages of disease.

METHODS

Selective laser trabeculoplasty was performed with 50 ± 5 laser spots in 180 degrees or with 100 ± 10 spots in 360 degrees. The laser power was titrated to either just below the cavitation bubble level ("standard energy") or to a level producing cavitation bubbles at 50% to 75% of laser applications ("high energy"). Thus, 4 different treatment protocols were included - 180/standard, 180/high, 360/standard, and 360/high. The study adhered as close as possible to regular clinical management, but within a scientific framework.

MAIN OUTCOME MEASURES

Reduction of intraocular pressure (IOP) 1 to 6 months after SLT. The proportion of patients achieving a 20% IOP reduction without any further intervention. Time to glaucoma treatment escalation in a Kaplan-Meier survival analysis.

RESULTS

SLT performed with the 360/high protocol was shown to be superior regarding all primary endpoints. The IOP reduction 1 to 6 months after SLT was 5.4 mmHg in the 360/high group, compared to 3.4, 3.2, and 4.2 mmHg with the 180/standard, 180/high, and 360/standard protocols, respectively (P < 0.001). Furthermore, the success rate after 6 months was significantly higher -58.3%, compared with 30.2%, 29.3%, and 41.7% (P < 0.001). The median time to glaucoma treatment escalation was more than twice as long with 360/high SLT -1323 days, compared to 437 days, 549 days, and 620 days (P < 0.001). Although postoperative discomfort was more frequent with the 360/high protocol, symptoms were generally mild and transient. Adverse events were rare in all groups.

CONCLUSIONS

The magnitude and longevity of SLT results increases substantially if SLT is performed according to the 360/high protocol, without compromising safety. Therefore, we recommend that 360/high SLT be considered as standard treatment.

FINANCIAL DISCLOSURES

The authors have no proprietary or commercial interest in any materials discussed in this article.

Outcomes of gonioscopy-assisted transluminal trabeculotomy in primary congenital glaucoma treatment: a retrospective study

BACKGROUND

This retrospective study aimed to evaluate the efficacy and safety of gonioscopy-assisted transluminal trabeculotomy (GATT) in Chinese patients with primary congenital glaucoma (PCG) and identify factors influencing surgical success.

METHODS

Fourteen patients (24 eyes) diagnosed with PCG who underwent gonioscopy-assisted transluminal trabeculotomy were recruited, and data on intraocular pressure (IOP), antiglaucoma medication, surgery-related complications, and additional treatments were collected during preoperative and postoperative visits. Surgical success was defined as IOP ≤ 21 mmHg and a reduction of > 30% from baseline, with (partial success) or without (complete success) antiglaucoma medication.

RESULTS

Mean preoperative IOP was 30.41 ± 6.09 mmHg. At the final visit, mean IOP reduction was 16.1 ± 9.1 mmHg (52%), and 19 of 24 eyes were topical medication-free. IOP was significantly decreased at each postoperative visit compared with baseline (P < 0.05 for all time points). Cumulative proportions of complete and partial success were 79.2% and 95.8%, respectively, at three years postsurgery. Patients without prior antiglaucoma procedures, without postoperative IOP spikes, and those undergoing complete trabeculotomy exhibited improved surgical prognosis. No permanent vision-threatening complications occurred in the 24 eyes by the end of the respective follow-ups.

CONCLUSION

Gonioscopy-assisted transluminal trabeculotomy emerged as a safe and effective procedure for PCG treatment, characterized by outstanding IOP reduction efficacy and high surgical success rates.

Twelve-month outcomes of Kahook dual blade goniotomy combined with cataract surgery in Latino patients

PURPOSE

To evaluate 12 month surgical outcome of Kahook Dual Blade (KDB) goniotomy in combination with cataract surgery in Latino patients with open angle glaucoma (OAG) and ocular hypertension (OHT).

METHODS

This retrospective study included 45 eyes of 40 patients who underwent KDB goniotomy combined with cataract extraction from January 2016 to September 2020 at two centers in South America. Primary outcome was surgical success defined as ≥ 20% intraocular pressure (IOP) reduction or ≥ 1 medication reduction from preoperative without additional IOP-lowering procedures and an IOP ≥ 5 mmHg or ≤ 21 mmHg. Additionally, we used 2 cutoffs values for success of IOP ≤ 18 and ≤ 15 mmHg. Secondary outcomes included: IOP, medication use, best corrected visual acuity, complications and failure-associated factors.

RESULTS

Success rates at 12 months with cutoff limits of 21, 18 and 15 mmHg were 84.3%, 75.6% and 58.7%, respectively. At 12 months, mean preoperative IOP significantly decreased from 19.23 ± 0.65 mmHg on 2.3 ± 1.0 medications to 14.33 ± 0.66 mmHg on 0.6 ± 0.9 medications (p < 0.001) , with 62% of eyes free of hypotensive medication. Eyes that developed postoperative IOP spikes showed a higher risk for failure using the cutoff limit of IOP ≤ 18 mmHg with a hazard ratio of 3.6 (95% confidence interval [CI], 1.80-7.13; p < 0.001). There were no serious ocular adverse events.

CONCLUSIONS

KDB combined with cataract extraction showed safety and efficacy for decreasing IOP in OAG and OHT Latino patients. Additionally, dependence on medications was reduced significantly after surgery.

Trabeculectomy in Eyes With High Myopia

PRCIS

Primary trabeculectomy was safe and effective at lowering intraocular pressure (IOP) in patients with primary open angle glaucoma and high myopia.

PURPOSE

To investigate the efficacy and safety of trabeculectomy in patients with glaucoma and high myopia.

PATIENT AND METHODS

Retrospective case-control study. Glaucomatous patients with high myopia undergoing primary trabeculectomy surgery with at least 1 year of follow-up were compared with an age-matched control group without high myopia undergoing the same procedure. Surgical success was defined as: IOP ≤ 15 mm Hg with (qualified) or without (complete) antiglaucoma medications and at least 20% reduction from baseline IOP at the end of 48 months of follow-up.

RESULTS

We included a total of 90 eyes from 90 patients (45 eyes with high myopia and 45 controls). Within the 90 eyes, 70 eyes underwent trabeculectomy and 20 eyes underwent combined phacoemulsification and trabeculectomy. Although patients with high myopia had higher chances for failure (37% vs. 22%) compared with controls, the difference was not statistically significant ( P =0.067). In the multivariable analysis, patients of African descent ( P =0.043) and those with juvenile glaucoma ( P =0.001) had more chances of failure, even after adjusting for myopia. There was no statistically significant difference between complication rates in both groups.

CONCLUSION

Trabeculectomy was effective in reducing IOP in patients with high myopia and glaucoma, without the additional risk of complications compared with a control group.

Aqueous Shunts with Extraocular Reservoir for Open-Angle Adult Glaucoma: A Report by the American Academy of Ophthalmology

PURPOSE

To evaluate the recently published literature on the efficacy and safety of the use of aqueous shunts with extraocular reservoir for the management of adult open-angle glaucomas (OAGs).

METHODS

A search of peer-reviewed literature was last conducted in April 2023 of the PubMed database and included only articles published since the last aqueous shunt Ophthalmic Technology Assessment, which assessed articles published before 2008. The abstracts of these 419 articles were examined, and 58 studies were selected for full-text analysis. After inclusion and exclusion criteria were applied, 28 articles were selected and assigned ratings by the panel methodologist according to the level of evidence. Twenty-five articles were rated level I and 3 articles were rated level II. There were no level III articles.

RESULTS

Implantation of aqueous shunts with extraocular reservoir can lower intraocular pressure (IOP) by between one-third and one-half of baseline IOP, depending on whether it is undertaken as the primary or secondary glaucoma surgery. Success rates for aqueous shunts were found to be better than for trabeculectomies in eyes with prior incisional surgery. Conversely, in eyes without prior incisional surgery, implantation of aqueous shunts was found to have an overall lower success rate as the primary glaucoma procedure compared with trabeculectomy. Although both valved and nonvalved aqueous shunts with extraocular reservoir were effective, the nonvalved device generally achieved slightly lower long-term IOPs with fewer glaucoma medications and less need for additional glaucoma surgery. Both devices slow the rates of visual field progression with efficacy comparable with that of trabeculectomy. Early aqueous humor suppression after aqueous shunt implantation is recommended for the management of the postoperative hypertensive phase and long-term IOP control. No strong evidence supports the routine use of mitomycin C with aqueous shunt implantation for OAG.

CONCLUSIONS

Implantation of aqueous shunts with extraocular reservoir, including valved or nonvalved devices, has been shown to be an effective strategy to lower IOP. Strong level I evidence supports the use of aqueous shunts with extraocular reservoir by clinicians for the management of adult OAG.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

The gonio scratch study: methodology of a multicenter clinical trial establishing a new minimally invasive glaucoma surgery

There are numerous surgical procedures for glaucoma. Minimally invasive glaucoma surgery is becoming popular; however, the disadvantage is the high incidence of anterior chamber hemorrhage. Heavy bleeding can also lead to increased intraocular pressure (IOP) postoperatively. Gonio scratch is a surgical procedure that improves aqueous humor outflow by rubbing off deposits on the trabecular meshwork with a Diamond Dusted Sweeper. As the conjunctiva and trabecular meshwork are not incised, no postoperative bleeding is expected, and the IOP spike will be minimal. We designed this study to determine the efficacy and safety of gonio scratch. This is an on-going multicenter, prospective, clinical trial. Patients who are scheduled for glaucoma surgery with or without cataract surgery are being enrolled. A total of 80 eyes will be recruited in the Hiroshima University Hospital, Miyoshi Eye Clinic, Yokoyama Retina Clinic, and Kusatsu Eye Clinic. All patients will undergo gonio scratch. When combined with cataract surgery, gonio scratch is performed after the intraocular lens is inserted. The primary study endpoint is the change in IOP from baseline to 1 year after surgery. The secondary endpoints are complications, number of glaucoma medications, surgical time, and changes in visual acuity and the visual field. This study protocol was approved by the institutional review board of Hiroshima University. The trial results will be shared with the scientific community at international conferences and by publication in a peer-reviewed journal. Trial registration number is jRCTs062200003.

Minimally Invasive Bleb Surgery for Glaucoma: A Health Technology Assessment

Background

Glaucoma is the term for a group of eye disorders that causes progressive damage to the optic nerve, which can lead to visual impairment and, potentially, irreversible blindness. Minimally invasive bleb surgery (MIBS) reduces eye pressure through the implantation of a device that creates a new subconjunctival outflow pathway for eye fluid drainage. MIBS is a less invasive alternative to conventional/incisional glaucoma surgery (e.g., trabeculectomy). We conducted a health technology assessment of MIBS for people with glaucoma, which included an evaluation of effectiveness, safety, the budget impact of publicly funding MIBS, and patient preferences and values.

Methods

We performed a systematic literature search of the clinical evidence. We assessed the risk of bias of each included study using the Cochrane Risk of Bias 1.0 tool for randomized controlled trials (RCTs) and the Risk of Bias Assessment tool for Nonrandomized Studies (RoBANS) for comparative observational studies, and the quality of the body of evidence according to the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) Working Group criteria. We conducted an economic literature search and we estimated the budget impact of publicly funding MIBS in Ontario. We did not conduct a primary economic evaluation due to the limited long-term effectiveness data. We summarized the preferences and values evidence from previous health technology assessments to understand the perspectives and experiences of patients with glaucoma.

Results

We included 41 studies (2 RCTs and 39 comparative observational studies) in the clinical evidence review. MIBS may reduce intraocular pressure and the number of medications used, but we are uncertain if MIBS results in outcomes similar to trabeculectomy (GRADE: Moderate to Very low). Compared with trabeculectomy, MIBS may result in fewer follow-up visits and interventions, and adverse events (GRADE: Moderate to Very Low). MIBS may also reduce intraocular pressure and the number of antiglaucoma medications used, compared with other glaucoma treatments, but the evidence is uncertain (GRADE: Very low). Our economic evidence review identified two directly applicable studies. The results of these studies indicate that the cost-effectiveness of MIBS is highly uncertain, and the cost of glaucoma interventions are likely to vary across provinces. The annual budget impact of publicly funding MIBS in Ontario ranged from $0.11 million in year 1 to $0.67 million in year 5, for a total 5-year budget impact estimate of $1.93 million. Preferences and values evidence suggests that fear of ultimate blindness and difficulty managing medication for glaucoma led patients to explore other treatment options such as MIBS. Glaucoma patients found minimally invasive glaucoma surgery (MIGS) procedure beneficial, with minimal side effects and recovery time.

Conclusions

Minimally invasive bleb surgery reduces intraocular eye pressure and the number of antiglaucoma medications needed, but we are uncertain if the outcomes are similar to trabeculectomy (GRADE: Moderate to Very low). However, MIBS may be safer than trabeculectomy (GRADE: Moderate to Very low) and result in fewer follow-ups (GRADE: Moderate to Very low). MIBS may also improve glaucoma symptoms compared with other glaucoma treatments, but the evidence is very uncertain (GRADE: Very low).We estimate that publicly funding MIBS would result in an additional cost of $1.93 million over 5 years. Patients who underwent MIGS procedures found them to be generally successful and beneficial, with minimal side effects and recovery time. We could not draw conclusions about specific MIBS procedures or long-term outcomes.

A deep learning approach to investigate the filtration bleb functionality after glaucoma surgery: a preliminary study

PURPOSE

To distinguish functioning from failed filtration blebs (FBs) implementing a deep learning (DL) model on slit-lamp images.

METHODS

Retrospective, cross-sectional, multicenter study for development and validation of an artificial intelligence classification algorithm. The dataset consisted of 119 post-trabeculectomy FB images of whom we were aware of the surgical outcome. The ground truth labels were annotated and images splitted into three outcome classes: complete (C) or qualified success (Q), and failure (F). Images were prepared implementing various data cleaning and data transformations techniques. A set of DL models were trained using different ResNet architectures as the backbone. Transfer and ensemble learning were then applied to obtain a final combined model. Accuracy, sensitivity, specificity, area under the ROC curve, and area under the precision-recall curve were calculated to evaluate the final model. Kappa coefficient and P value on the accuracy measure were used to prove the statistical significance level.

RESULTS

The DL approach reached good results in unraveling FB functionality. Overall, the model accuracy reached a score of 74%, with a sensitivity of 74% and a specificity of 87%. The area under the ROC curve was 0.8, whereas the area under the precision-recall curve was 0.74. The P value was equal to 0.00307, and the Kappa coefficient was 0.58.

CONCLUSIONS

All considered metrics supported that the final DL model was able to discriminate functioning from failed FBs, with good accuracy. This approach could support clinicians in the patients' management after glaucoma surgery in absence of adjunctive clinical data.

Difficult decisions, filtration surgery, and the heartbreak of the numerator

A 70-year-old man had progressive and severe glaucoma in each eye. He was intolerant to dorzolamide, brimonidine, and netarsudil. Each eye had prior selective laser trabeculoplasty (SLT) as well as phacoemulsification plus minimally invasive glaucoma surgery (MIGS) 6 years before current presentation (iStent [Glaukos Corp.] in the right eye and Cypass [Alcon Laboratories, Inc.] in the left eye). Postoperative acuities were 20/20 and 20/25 in the right and left eyes, respectively. When his left eye progressed with loss of central acuity despite peak intraocular pressures (IOPs) in the middle to upper teens, neuro-ophthalmology consultation was obtained (Figure 1JOURNAL/jcrs/04.03/02158034-202401000-00017/figure1/v/2023-12-22T124801Z/r/image-tiff). That workup included magnetic resonance imaging scan and hematologic screening, but all results were negative, and the neuro-ophthalmic consultant concluded that the vision loss was likely on the basis of glaucoma. Accordingly, a trabeculectomy was performed in the left eye achieving consistent IOPs in the range of 7 to 10 mm Hg without medications, rending the left eye stable since the filtration surgery nearly 2 years previously. The right eye continued to progress both subjectively and objectively, and on recent examination, the IOP measured 20 mm Hg and 09 mm Hg in the right and left eyes, respectively (Figure 2JOURNAL/jcrs/04.03/02158034-202401000-00017/figure2/v/2023-12-22T124801Z/r/image-tiff). Medications included timolol and latanoprostene bunod in the right eye only. Central corneal thickness was 526 μm and 527 μm in the right and left eyes, respectively. The visual acuity now measured 20/25 in the right eye and 20/250 in the left eye. The vertical cup-to-disc ratio was 0.9 in the right eye and 1.0 in the left eye. Gonioscopy revealed a wide open angle in each eye with a patent sclerostomy superiorly in the left eye. The conjunctiva and sclera were healthy and without scarring in the right eye. The bleb in the left eye was diffuse, lightly vascularized, and seidel negative. Axial length (AL) was 26.88 μm in the right eye and 26.77 μm in the left eye. The patient was in good health and was not anticoagulated. An extensive discussion ensued about the best course of action for the right eye. How would you proceed in managing definite progression in this individual's right eye, knowing that he had lost fixation in his left eye at similar pressures?