Efficacy and safety of Usights UC100 illuminated microcatheter in microcatheter-assisted trabeculotomy

AIM:To evaluate the efficacy and safety of Usights UC100 illuminated microcatheter in microcatheter-assisted trabeculotomy(MAT).METHODS:Totally 10 eyes of 10 patients with primary open angle glaucoma(POAG)who underwent MAT facilitated by Usights UC100(5 eyes)or iTrack(5 eyes)were reviewed.The success of this surgery was defined as intraocular pressure(IOP)<22 mm Hg with>30%reduction,without oral glaucoma medications,or additional glaucoma surgery.RESULTS:The mean pre-operative IOP was 25.38±10.22 mm Hg in the Usights UC100 group and 19.98±3.87 mm Hg in the iTrack group.MAT was achieved in all eyes in both groups.The success rates for the Usights UC100 group and iTrack groups were in all and 4 eyes,respectively.Both microcatheters produced a statistically significant reduction in IOP,and eyes using Usights UC100 achieved a lower IOP than the iTrack group at 3mo followup(12.58±1.52 and 14.84±1.89 mm Hg,respectively),but no statistical significance was there.No severe side effects were observed in either group.CONCLUSION:MAT using Usights UC100 or iTrack both achieve significant pressure reduction in cases of POAG,and Usights UC100 is as safe as iTrack.

Clinical significance of episcleral venous fluid wave in gonioscopy-assisted transluminal trabeculotomy

AIM:To evaluate the clinical significance of checking episcleral venous fluid wave(EVFW)during gonioscopyassisted transluminal trabeculotomy(GATT)in patients with open angle glaucoma(OAG).METHODS:This retrospective case series study comprised 30 patients(45 eyes)with OAG underwent GATT.The location and extent of EVFW were examined and graded after intraoperative compression flushing of the anterior chamber angle during the operation.Patients were followed up for 1y.A complete success for surgery is defined as a postoperative intraocular pressure(IOP)<18 mm Hg without any anti-glaucoma medication.IOP<18 mm Hg with less than two anti-glaucoma medications is defined as qualified success,while the control of IOP requiring three anti-glaucoma medications is considered as unsuccess.RESULTS:The mean IOP was 35.38±7.16 mm Hg before surgery and 15.52±4.22 mm Hg 1y after surgery(P<0.01).The average number of anti-glaucoma medication was 2.8±1.2(2-4)preoperation and 0.6±1.3(0-3)1y postoperation(P<0.01).The success rate of the operation was 93.33%.Complete success rate was 66.67%,qualified success rate was 26.67%,and 6.66%of unsuccessful cases required reoperation.EVFW of all cases was grade 2-4,and the percentages of grade 2,3 and 4 were 33.33%,40.0%and 26.67%,respectively.The distribution and percentage of EVFW were inferior(36%),nasal(28%),superior(20%),and temporal(16%).The EVFW grade of complete success patients was 3.4±0.6(3-4),and that of qualified success patients was 2.6±1.0(2-4).The larger the range of EVFW,the lower the IOP,and the better the IOP reduction effect.CONCLUSION:During GATT surgery,pressurized irrigation of anterior chamber to check EVFW can reduce the outflow resistance of aqueous humor and increase the effect of postoperative IOP.The range of EVFW is negatively correlated with postoperative IOP.Therefore,EVFW may be a valuable prognostic indicator for the success of GATT surgery.

One-year outcomes and predictable factors for microhook ab interno trabeculotomy

AIM: To investigate the one-year outcomes and factors that influence the results of microhook ab interno trabeculotomy(μLOT). METHODS: The medical records of consecutive patients with open angle glaucoma who underwent μLOT(including combination of μLOT and cataract surgery) between Februar y 2018 and July 2019 were retrospectively reviewed. Surgical success was defined as the following: an intraocular pressure(IOP)≤21 mm Hg or IOP≤preoperative IOP with a reduced number of glaucoma eye drops, without additional glaucoma surgery, and assessed using KaplanMeier survival analysis. A multivariate Cox proportionalhazards regression model was used to investigate the factors associated with surgical failure.RESULTS: The 59 eyes of 59 patients comprising 28 eyes with primary open angle glaucoma(POAG) and 31 with secondary open angle glaucoma(SOAG) were included. The mean IOP and number of glaucoma eye drops significantly decreased from 25.3±7.2 mm Hg and 3.9±1.1, preoperatively to 16.1±4.4 mm Hg(P<0.01) and 2.1±1.8(P<0.01),respectively, 12 mo postoperatively, with a cumulative success rate of 63.1%. The one-year success rate was significantly higher in POAG eyes than in SOAG eyes(80.0% vs 48.0%;P=0.011, log-rank test). Multivariate analyses revealed SOAG [P=0.017, adjusted hazard ratio(a HR): 3.468, 95%CI: 1.246-9.654] and the postoperative IOP spike(IOP>25 mm Hg within 2 wk post-surgery;P<0.001, a HR: 5.382, 95%CI:2.113-13.707) as independent factors associated with surgical failure.CONCLUSION: The μLOT is a good treatment option for POAG eyes. However, the postoperative course should be carefully followed in cases with postoperative IOP spike.

Systematic review and Meta-analysis of treating open angle glaucoma with gonioscopy-assisted transluminal trabeculotomy

●AIM:To systematically review and Meta-analyze studies of managing open angle glaucoma(OAG)with gonioscopyassisted transluminal trabeculotomy(GATT)and to evaluate its effectiveness and safety.●METHODS:Eligible studies were retrieved and screened from five main electronic databases.Mean difference(MD)was hired to show the pooled effectiveness of intraocular pressure(IOP)and medication decrease achieved by GATT.In addition,combined surgical success and reoperation rates were calculated,and complications were also summarized.●RESULTS:Ten studies were included for systematic review,but one study was not pooled for Meta-analysis due to the repeated data.The combined IOP decrease after GATT was 9.81 mm Hg(95%CI:7.98-11.63 mm Hg)which showed significant reduction from the baselines(Z=10.52,P<0.0001).Similarly,the number of medications after GATT also decreased distinctly compared with that of medication before the surgery(Z=9.09,P<0.0001),and the pooled medication decrease was 1.68(95%CI:1.31-2.04).In addition,the combined surgical success rate was 85%,while the pooled reoperation rate was 20%.Sightthreatening complications occurred scarcely,whereas the pooled occurrence rate of hyphemia was as high as 36.0%.●CONCLUSION:GATT could effectively lower IOP and decrease medications for patients with OAG.Moreover,the procedure appears to be a safe and promising treatment for OAG due to its minimally-invasive and conjunctiva-sparing nature.

Comparison of minimally invasive glaucoma surgery with trabecular micro-bypass stent and microhook ab interno trabeculotomy performed in conjunction with cataract surgery

AIM: To evaluate the effectuality and safety of cataract surgery combined with either ab interno trabeculotomy by the microhook(μLOT) or a single i Stent? trabecular bypass implantation(i Stent) in eyes with cataract and mild-tomoderate glaucoma. METHODS: This study enrolled subjects with mild-tomoderate open angle glaucoma with visually significant cataract who used two or more ophthalmic antiglaucoma agents between 60 and 90 y of age. Patients underwent cataract surgery cooperated with either implantation of an i Stent(i Stent-phaco) or excisional goniotomy with the μLOT(μLOT-phaco). Patients underwent μLOT-phaco in the eye with lower the mean deviation, according to the Humphrey field analyzer, while i Stent-phaco was carried out on the other eye. Intraocular pressure(IOP) pre-and post-surgery, alterations in anterior chamber flare(ACF), and corneal endothelial cell density(ECD) were estimated.RESULTS: Twenty subjects were enrolled(mean age: 73.6±7.3 y). The mean medicated preoperative IOP was 16.7 mm Hg in the μLOT and 16.2 mm Hg in the i Stent eyes. The mean final IOP at 12 mo was 13.6 mm Hg in the μLOT eyes and 13.6 mm Hg in the i Stent eyes, representing a 17.8% and 17.2% reduction, respectively. The preoperative ACF in the μLOT eyes was 9.5 pc/ms and it returned to normal in 30 d postoperatively, with a value of 11.4 pc/ms. In the i Stent eyes, ACF was 9.6 pc/ms preoperatively and it returned to normal by 7 d postoperatively(11.2 pc/ms atday 7), demonstrating that postoperative inflammation was less in the i Stent eyes. The corneal ECD in both groups was not significantly decreased.CONCLUSION: In this study, i Stent and μLOT are both effective through 12 mo of follow-up. Safety is more favorable in the i Stent eyes, based on early anterior chamber inflammation.

Full-thickness scleral incisions technique for the treatment of a cyclodialysis cleft following ab interno trabeculotomy

Dear Editor, I am Dr.Daniela Alvarez-AscenciofromtheGlaucoma Department at Asociacion Para Evitar la Ceguera (APEC)in Mexico City, Mexico. I write to present a successful case of cyclodyalisis repair in a direct visualization technique that was performed on a patient after a microincisional glaucoma surgery (MIGS) complication.

Efficacy of microcatheter-assisted trabeculotomy on secondary glaucoma after congenital cataract surgery

AIM: To evaluate efficacy of microcatheter-assisted trabeculotomy(MAT) in eyes with secondary glaucoma after congenital cataract surgery and explore its correlation with the different degree of trabeculotomy. METHODS: A retrospective analysis was conducted on patients who underwent the said procedure between September 2019 and September 2020. The patients were classified into two groups according to the degree of trabeculotomy(group 1: ≤240-degree;group 2: 240–360-degree). The intraocular pressure(IOP) and antiglaucoma drugs before and after operation was collected during the 12-month follow-up. RESULTS: Totally 27 eyes of 25 patients were included: 11(40.7%) eyes in group 1 and 16(59.3%) eyes in group 2. The mean IOP of all patients was 34.67±9.18 mm Hg preoperatively and 8.74±4.32, 9.95±5.65, 14.39±5.30, 16.02±4.37, 15.82±3.28, and 16.19±3.56 mm Hg 1 d, 1 wk, 1, 3, 6, and 12 mo after surgery, respectively. In all patients, there were significant differences in IOP at each time point(F=65.614, P<0.01). In each group, IOP after surgery was lower than that before surgery(all P<0.01), but there was no difference in the rate of IOP reduction between the two groups(P=0.246). Furthermore, the amount of anti-glaucoma medications reduced to 0.30±0.67(0–2) at 12 mo from 2.63±0.49(2–3) preoperatively(P<0.01), and there was no difference between the two groups(P>0.05). At the end of follow-up, the partial success rate was 81.8% in group 1 vs 93.75% in group 2(P=0.549). Various amount of intraoperative and postoperative hyphema occurred in all eyes, which spontaneously absorbed or cleaned through paracentesis and irrigation. No other serious complications was observed.CONCLUSION: MAT can effectively reduce IOP in patients with secondary glaucoma after congenital cataract surgery with a high success rate and safety. And it can be used as the first choice for the treatment of secondary glaucoma after surgery for congenital cataracts.

Therapeutic effect analysis on the treatment of congenital glaucoma through modified combined trabeculotomy-trabeculectomy

AIM： To evaluate the therapeutic effect and the safety of the treatment of congenital glaucoma through modified combined trabeculotomy-trabeculectomy. METHODS： The clinical data of 27 cases （altogether 42 eyes）, which included 7 cases of infants （10 eyes） and 20 cases of teenagers （32 eyes）, of congenital glaucoma undertook modified combined trabeculotomy trabeculectomy were analyzed retrospectively. The parameters evaluated included the post operation visual acuity, the anterior chamber, the filtering bleb, the intraocular pressure, the C/D ratio, visual field, the retinal nerve fiber layer changes and the complications. RESULTS： The follow-up period was 1 to 29mo, averaging 13.3 ±7.7mo. Upon the last visit after the operation, functional filtering blebs developed in all the involved eyes. The intraocular pressure was controlled under 21 mm Hg, which was decreased by 60% when compared with that before the operation, without using any medication. There were no significant changes in the post operation visual acuity and the retinal nerve fiber layer thickness before and after the operation in teenager group （P〉0.05）, and both the post operation C/D ratio and the visual field mean defect （MD） were reduced compared with those before the operation （P〈0.05）. There were no severe complications in any of the patients. CONCLUSION： The modified combined trabeculotomy- trabeculectomy can effectively reduce the intraocular pressure and control the development of glaucoma in cases of congenital glaucoma. It is a safe and effective operative method for the treatment of congenital glaucoma

Surgical Outcomes of Trabeculotomy in Newborns with Primary Congenital Glaucoma

Background： Early surgical intervention is required for the primary congenital glaucoma （PCG）. There are currently few reports on the surgical outcomes in infants with PCG. This study aimed to evaluate the efficacy and safety oftrabeculotomy and the postoperative visual outcomes in Chinese newborns with PCG within 4 weeks of birth. Methods： A total of 21 eyes of 12 patients with PCG who underwent primary trabeculotomy within 4 weeks of birth were retrospectively studied. Preoperative and postoperative intraocular pressure （lOP）, corneal clarity and diameter, axial length and optic disc cupping, visual acuity and postoperative refractive error, success rates, and complications were evaluated. Kaplan-Meier survival analysis was applied to evaluate the success rates. Results： The mean follow-up time was 46.9 ~ 34.4 months （range： 12-122 months）. The postoperative lOP was significantly lower than the preoperative lOP at all of the follow-up visits （P 〈 0.001 ）. The complete success rates for all eyes at 1,2, 3, and 5 years postoperatively were 90.5%, 85.7%, 85.7%, and 85.7%, respectively. The lOPs of the three patients who needed antiglaucomatous medications postoperatively were also well controlled. At the last visit, the cornea became clear, and the cup-to-disc ratio decreased significantly （P = 0.01） although the horizontal corneal diameter did not change significantly （P = 0.11 ）. Visual acuities were able to be recorded in eight eyes at the last visit, among which six eyes had a best-corrected visual acuity of 20/40 or better. There were no severe intraoperative or postoperative complications. Conclusions： Trabeculotomy proves to be a safe and effective treatment in reducing lOP in this group of Chinese newborns with PCG. The outcomes of vision function were satisfactory in most of the patients.

Modified trabeculotomy for primary congenital glaucoma

In traditional trabeculotomy,a radial incision is performed at the corneoscleral transition zone to locate the Schlemm＇s canal.However,in some conditions,finding the Schlemm＇s canal is difficult because of the enlargement of the comea,developmental anomalies of the angle,etc.In our study,we performed a modified trabeculotomy,to locate the Schlemm＇s canal easily and accurately and evaluated the outcomes.

Cost analysis of childhood glaucoma surgeries using the US Medicaire allowable costs

AIM: To analyze and calculate the relative cost of various childhood glaucoma surgical interventions per mm Hg intraocular pressure(IOP) reduction($/mm Hg).METHODS: Representative index studies were reviewed to quantitate the reduction of mean IOP and glaucoma medications for each surgical intervention in childhood glaucoma. A US perspective was adopted, using Medicare allowable costs to calculate cost/mm Hg IOP reduction($/mm Hg) at 1y postoperatively.RESULTS: At 1y postoperatively, the cost/mm Hg IOP reduction was $226/mm Hg for microcatheter-assisted circumferential trabeculotomy, $284/mm Hg for cyclophotocoagulation, $288/mm Hg for conventional ab-externo trabeculotomy, $338/mm Hg for Ahmed glaucoma valve, $350/mm Hg for Baerveldt glaucoma implant, $351/mm Hg for goniotomy, and $400/mm Hg for trabeculectomy.CONCLUSION: Microcatheter-assisted circumferential trabeculotomy is the most cost-efficient surgical method to lower IOP in childhood glaucoma, while trabeculectomy is the least cost-efficient surgical method.

Novel CYP1B1 mutations and a possible prognostic use for surgical management of congenital glaucoma

AIM: To identify CYP1B1 gene mutations and evaluate their possible role as a prognostic factor for success rates in the surgical management of Egyptian congenital glaucoma patients.METHODS: Totally 42 eyes of 29 primary congenital glaucoma patients were operated on with combined trabeculotomy/trabeculectomy with mitomycin-C and followed up at 1 d, 1 wk, 1, 6 and 12 mo postoperatively. Genomic DNA was extracted from peripheral blood leukocytes. Coding regions of CYP1B1 gene were amplified using 13 pairs of primers, screened for mutations using single-strand conformation polymorphism followed by sequencing of both strands. Efficacy of the operation was graded as either a success [maintaining intraocular pressure(IOP) less than 21 mm Hg with or without antiglaucoma medication], or a failure(IOP more than 21 mm Hg with topical antiglaucoma medications). RESULTS: Seven novel mutations out of a total of 15 different mutations were found in the CYP1B1 genes of 14 patients(48.2%). The presence of CYP1B1 gene mutations did not correlate with the failure of the surgery(P=0.156, odds ratio=3.611, 95%CI, 0.56 to 22.89); while the positive consanguinity strongly correlated with failure of the initial procedure(P=0.016, odds ratio=11.25, 95%CI, 1.57 to 80.30). However, the Kaplan-Meier survival analysis revealed a significantly lower time of IOP control in the subgroup with mutations in CYP1B1 versus the congenital primary glaucoma group without mutations(log rank test, P=0.015).CONCLUSION: Seven new CYP1B1 mutations are identified in Egyptian patients. Patients harboring confirmed mutations suffered from early failure of the initial surgery. CYP1B1 mutations could be considered as a prognostic factor for surgery in primary congenital glaucoma.

Ethylenediaminetetraacetic Acid Chelation for Band Keratopathy before Ab Interno Glaucoma Surgery

An 87-year-old woman with primary open-angle glaucoma presented to our hospital. Although the combined cataract and minimally invasive glaucoma surgeries (MIGS) were an appropriate surgical option, the presence of band keratopathy made it difficult to perform ab interno glaucoma surgery in her right eye (OD);therefore, the corneal opacity was removed using ethylenediaminetetraacetic acid (EDTA) chelation procedure. One month after chelation, microhook ab interno trabeculotomy and cataract surgery were performed successfully. Clear intraoperative visualization of the angle structures is critical for the success of these MIGS procedures. In glaucomatous eyes that require MIGS, EDTA chelation is a good neoadjuvant therapy for coexisting band keratopathy.

Childhood Glaucoma: An Overview

Several types of childhood glaucoma exist, and the terminology is based on the time of onset of disease and its potential cause. Though childhood glaucoma occurs less commonly than adults but can lead to permanent visual damage due to amblyopia, optic neuropathy or refractive error. A detailed evaluation should be done to establish diagnosis. Medical therapy has a limited role and surgery remains main modality for treatment. Childhood glaucoma is a treatable disease, if early diagnosis is established and therapeutic intervention done in time. In children with low vision efforts should be there to maintain residual vision and visual rehabilitation with low vision aids should be done.

Current review of Excimer laser Trabeculostomy

Background:Excimer laser trabeculostomy(ELT)is a microinvasive glaucoma surgery(MIGS)that creates multiple laser channels through the trabecular meshwork using a cold laser system,which minimizes tissue fibrosis and aids in bypassing the main area of resistance to aqueous outflow.The purpose of this review is to evaluate the current body of evidence surrounding ELT in terms of efficacy and review the safety profile of the procedure.Main text:Studies screened had to show clear inclusion and exclusion criteria as well as well-defined outcome measures.PubMed,MEDLINE,EMBASE and the Cochrane Controlled Trial Database were searched.Preferred Reporting Items of Systematic Reviews(PRISMA)guidelines were used to assess for study quality and for any bias.Sixty-four articles were initially identified with 18 meeting preliminary screening criteria.Ultimately,8 studies met inclusion criteria and 2 additional non-referenced publications were also included:1 randomized control trial,4 prospective case series and 5 retrospective studies.Overall studies showed moderate intraocular pressure(IOP)lowering of between 20%and 40%from baseline without medication washout and mostly a decrease in glaucoma medications with few complications.Conclusion:Current literature shows a significant IOP-lowering effect of ELT with a favorable safety-profile in standalone cases or combined with cataract surgery.Limitations to these studies are the lack of controls and washout IOP.Overall,ELT is an attractive MIGS option that does not require any residual device remaining in the angle.