Review on the Management of Primary Congenital Glaucoma

Increasing the diagnostic yield of childhood glaucoma cases recruited into the 100,000 Genomes Project

Childhood glaucoma (CG) encompasses a heterogeneous group of genetic eye disorders that is responsible for approximately 5% of childhood blindness worldwide. Understanding the molecular aetiology is key to improving diagnosis, prognosis and unlocking the potential for optimising clinical management. In this study, we investigated 86 CG cases from 78 unrelated families of diverse ethnic backgrounds, recruited into the Genomics England 100,000 Genomes Project (GE100KGP) rare disease cohort, to improve the genetic diagnostic yield. Using the Genomics England/Genomic Medicine Centres (GE/GMC) diagnostic pipeline, 13 unrelated families were solved (13/78, 17%). Further interrogation using an expanded gene panel yielded a molecular diagnosis in 7 more unrelated families (7/78, 9%). This analysis effectively raises the total number of solved CG families in the GE100KGP to 26% (20/78 families). Twenty-five percent (5/20) of the solved families had primary congenital glaucoma (PCG), while 75% (15/20) had secondary CG; 53% of this group had non-acquired ocular anomalies (including iris hypoplasia, megalocornea, ectopia pupillae, retinal dystrophy, and refractive errors) and 47% had non-acquired systemic diseases such as cardiac abnormalities, hearing impairment, and developmental delay. CYP1B1 was the most frequently implicated gene, accounting for 55% (11/20) of the solved families. We identified two novel likely pathogenic variants in the TEK gene, in addition to one novel pathogenic copy number variant (CNV) in FOXC1. Variants that passed undetected in the GE100KGP diagnostic pipeline were likely due to limitations of the tiering process, the use of smaller gene panels during analysis, and the prioritisation of coding SNVs and indels over larger structural variants, CNVs, and non-coding variants.

Slow coagulation versus micropulse transscleral cyclophotocoagulation for refractory childhood glaucoma

PURPOSE

To compare the safety and efficacy of micropulse laser (MP-TSCP) and slow coagulation transscleral cyclophotocoagulation (TSCP) with a diode laser for reducing intraocular pressure (IOP) in patients with refractory childhood glaucoma (CG).

METHODS

Patients with CG and at least 12 months of medical chart data were included. Data on preoperative and postoperative outcomes were analyzed. The primary outcomes were an IOP of 6-21 mmHg and/or ≥ 20% reduction in the baseline value.

RESULTS

A total of 17 eyes were included. The preoperative mean IOP was 28 mmHg in the MP-TSCP and 29.9 mmHg in the TSCP. The mean IOP decreased significantly to 17.26 ± 3.27 mmHg in the MP-TSCP and 14.68 ± 5.79 mmHg TSCP at the last medical record. Three anti-glaucoma meds were administered to the eyes preoperatively in both groups. A mean of 1.02 eye drops was administered to the MP-TSCP and 2.06 to the TSCP. The number of medications decreased by 2.38 ± 1.55 in the MP-TSCP and 0.82 ± 1.68 in the TSCP. The median preoperative visual acuity (logMAR) was 1.51 ± 1.06 in the MP-TSCP and 1.87 ± 0.74 in the TSCP. The variation in mean visual acuity (logMAR) was -0.027 ± 0.05 in the MP-TSCP and -0.40 ± 0.58 in the TSCP. The most frequent complication was corneal decompensation (one - MP-TSCP and two - TSCP).

CONCLUSION

Both techniques were effective and relatively safe for reducing IOP. These techniques appear to extend the indications of cyclophotocoagulation in CG eyes and improve the functional prognosis.

Non-penetrating deep sclerectomy versus combined trabeculotomy-trabeculectomy in primary congenital glaucoma

Background

The primary mode of therapy in children with primary congenital glaucoma (PCG) and mild or no corneal edema is goniotomy, which has a high success rate. However, in developing countries, the diagnosis of PCG is usually delayed, and corneal cloudiness interferes with goniotomy. Therefore, trabeculotomy may be the best choice in such eyes. We compared the short-term efficacy and safety of primary combined trabeculotomy-trabeculectomy (primary CTT) with that of non-penetrating deep sclerectomy (NPDS) in managing PCG.

Methods

This prospective, randomized, comparative study included patients with PCG referred to Al-Azhar University Hospitals within a 1-year period. Eyes were randomly allocated to one of two groups: eyes in NPDS group underwent NPDS, and those in primary CTT group underwent primary CTT. Baseline and frequent postoperative assessments of intraocular pressure (IOP), cup-to-disc ratio (C/D ratio), corneal diameter, and axial length were performed for up to 6 months. The success rates were recorded in both groups.

Results

Forty eyes of 26 patients were included, with 20 eyes allocated to each group. The mean (standard deviation) age of all patients was 12.9 (9.5) months, with comparable ages and sex ratios between groups (both P > 0.05). Both groups demonstrated a significant reduction in IOP and C/D ratio at each postoperative visit compared to the baseline visit (all P < 0.001), with no significant difference detected between the groups (all P > 0.05), except for a significantly lower IOP in NPDS group at 1 month (P < 0.05). The corneal diameter and axial length were comparable between groups at baseline and remained unchanged at all postoperative visits (all P > 0.05). The groups had comparable success rates (P > 0.05). No serious complications were detected.

Conclusions

CTT and NPDS both yielded reasonable IOP control and reversal of cupping in eyes with PCG. We observed equal effectiveness of the surgical procedures without major safety concerns. Further large-scale clinical trials with longer follow-up periods are needed to verify our preliminary findings.

[Trabeculotomy (ab externo) as primary intervention for open-angle glaucoma : 5-year results]

BACKGROUND

The published results of trabeculotomy ab externo (TOT), as an outflow channel surgery in adults with open-angle glaucoma, are underrepresented in comparison with other pressure-lowering glaucoma procedures.

OBJECTIVE

To determine the long-term pressure lowering effect and complications of TOT as a stand-alone procedure or in combination with phacoemulsification with intraocular lens implantation (PIT) as a primary pressure-lowering procedure in adult patients with forms of chronic open-angle glaucoma.

METHOD

This was a retrospective analysis of 121 eyes of 106 patients wherby 90 eyes underwent TOT and 31 eyes underwent PIT. The follow-up period was 5 years. Follow-up was performed in the same center under standardized conditions. Preoperative as well as postoperative best-corrected distance visual acuity, intraocular pressure, pressure-lowering medication, and complications were recorded. For success criterion 1, the intraocular pressure was not allowed to exceed 17 mm Hg at any control. For success criterion 2, the intraocular pressure was allowed to be above 17 mm Hg at 1 control throughout the follow-up period.

RESULTS

Preoperative intraocular pressure in the TOT group was 25.92 mm Hg (SD 6.58) and 26.32 mm Hg (SD 6.06) in the PIT group. The annual cumulative success rates with pressure-lowering medications for success criterion 1 were 92.8%, 82.5%, 70.5%, 52.7% and 26.1%. For success criterion 2 these were 97.9%; 94.9%, 93.2%, 91.3%, and 89%. We found no relevant difference in pressure reduction between TOT and PIT. Without pressure-lowering medications, success rates were significantly lower for both success criteria. No serious complications occurred. The most common postoperative complication was spontaneously resorbable hyphema.

CONCLUSION

Performing TOT or PIT as a primary glaucoma procedure for chronic open-angle glaucoma in adults is reasonable, has a significant pressure-lowering effect and very low complication rate.

Genetics and Glaucoma: the state of the art

Glaucoma is the second leading cause of irreversible blindness worldwide. Although genetic background contributes differently to rare early-onset glaucoma (before age 40) or common adult-onset glaucoma, it is now considered an important factor in all major forms of the disease. Genetic and genomic studies, including GWAS, are contributing to identifying novel loci associated with glaucoma or to endophenotypes across ancestries to enrich the knowledge about glaucoma genetic susceptibility. Moreover, new high-throughput functional genomics contributes to defining the relevance of genetic results in the biological pathways and processes involved in glaucoma pathogenesis. Such studies are expected to advance significantly our understanding of glaucoma's genetic basis and provide new druggable targets to treat glaucoma. This review gives an overview of the role of genetics in the pathogenesis or risk of glaucoma.

Microcatheter-Assisted Circumferential Trabeculotomy After Failed Glaucoma Surgeries in Childhood Glaucoma

PURPOSE

To evaluate the outcomes of microcatheter-assisted trabeculotomy (MAT) in childhood glaucoma (primary congenital glaucoma [PCG], juvenile open-angle glaucoma [JOAG], and secondary childhood glaucoma [SCG]) after failed glaucoma surgery.

DESIGN

Retrospective interventional case series.

METHODS

Patients with childhood glaucoma who underwent MAT after failed glaucoma surgery with at least 12 months of follow-up were evaluated. Pre- and postoperative intraocular pressure (IOP) and the number of glaucoma medications were recorded and compared. Success was defined as an IOP ≤21 mm Hg with or without glaucoma medication. Analysis of variance was used to compare the glaucoma subgroups.

RESULTS

Forty-five eyes (42 patients) with a median follow-up period of 19 months were included. The median age at the time of MAT was 10 (range, 0.8-33) years. The mean number of previous surgeries was 1.3 ± 0.5. The IOP had significantly reduced from baseline in all PCG, JOAG, and SCG patients (27.9 ± 4.5 vs 16.3 ± 8.0 mm Hg, P = .001; and 30.8 ± 9.4 vs 13.5 ± 3.0 mm Hg, P < .001; and 31.5 ± 7.1 vs 16.5 ± 5.3 mm Hg, P = .001, respectively). Fewer glaucoma medications were needed after MAT in all 3 groups (each P < .001). At the last visit, the total success rates in PCG, JOAG, and SCG were 93.8%, 100%, and 88.9%, respectively. No severe complications were observed.

CONCLUSION

MAT can effectively manage PCG, JOAG, and SCG after failed surgeries, providing successful outcomes and no serious complications. Following failed glaucoma surgeries, MAT may offer these patients with childhood glaucoma an excellent opportunity to achieve IOP control.

Long-term Outcomes in Patients Undergoing Surgery for Primary Congenital Glaucoma between 1991 and 2000: A Single-Center Database Study

PURPOSE

To estimate the long-term surgical and visual outcomes in patients with primary congenital glaucoma (PCG) who completed at least 20 years of follow-up.

DESIGN

Retrospective study.

PARTICIPANTS

Two hundred twenty eyes of 121 patients undergoing surgery for PCG between January 1991 and December 2000 and who returned for a follow-up visit from January 2021 through January 2022.

METHODS

Retrospective review of medical records of patients who underwent primary combined trabeculotomy-trabeculectomy (CTT) without mitomycin C as an initial procedure. Success was defined as complete when intraocular pressure (IOP) was ≥ 6 mmHg and ≤ 21 mmHg without glaucoma medication and as qualified when up to 2 glaucoma medications were required. Failure was defined as uncontrolled IOP with more than 2 glaucoma medications, need for a second IOP-lowering procedure, chronic hypotony (IOP < 6 mmHg on 2 consecutive visits), or any sight-threatening complication. A mixed-effects model using maximum likelihood estimation was used in estimation of eye-based variables and to make comparisons between different visits. Kaplan-Meier survival analysis was used to estimate the probabilities of surgical and functional successes. Cox proportional hazards regression using sandwich clustered estimation was used to evaluate risk factors for failure and poor visual outcome.

MAIN OUTCOME MEASURES

Primary outcome measure was the proportion of patients who demonstrated complete success over the 20-year follow-up. Secondary outcome measures included rate of surgical failure and need for reoperation for glaucoma, visual acuity, refractive errors, risk factors for poor outcome, and complications.

RESULTS

Kaplan-Meier survival analysis revealed 1-year, 10-year, and 20-year complete success rates of 90.7%, 78.9%, and 44.5%, respectively. In univariate analysis, surgical failure was higher among patients with any additional non-glaucoma intraocular surgery. None of the clinical parameters were associated significantly with failure in multivariable analysis. Overall, the proportion of eyes with good, fair, and poor visual outcomes was 33.2%, 16.4%, and 50.4%, respectively. Myopia was seen in 68.9% eyes. Twenty-eight eyes of those who underwent primary CTT (14.4%) required second surgery for IOP control. No significant intraoperative complications occurred. Six eyes required enucleation because of painful blind eye.

CONCLUSIONS

In this large cohort of patients with PCG, CTT is a useful procedure. It provides good IOP control and moderate visual recovery that remained over a 20-year follow-up after surgery.

FINANCIAL DISCLOSURE(S)

The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Long-Term Results of Combined Trabeculotomy Trabeculectomy in Primary Congenital Glaucoma

PRCIS

Primary congenital glaucoma (PCG) in Tunisian children seems to be characterized by a high prevalence of inherited and advanced forms of the disease. Primary combined trabeculotomy trabeculectomy (CTT) allowed satisfactory long-term intraocular pressure (IOP) control and reasonable visual outcome.

PURPOSE

To report the long-term outcome of CTT as the initial glaucoma surgery in children with PCG.

METHODS

Retrospective analysis of children who underwent primary CTT for PCG between January 2010 and December 2019. The main outcome measures were IOP reduction, corneal clarity, complications, refractive errors, and visual acuity (VA). Success was defined as IOP <16 mm Hg without (complete) or with (qualified) antiglaucoma medication. The WHO criteria of vision loss were used to categorize visual impairment (VI).

RESULTS

Of 62 patients, 98 eyes were enrolled. At the last follow-up, the mean IOP was reduced from 22.7 ± 4.0 mm Hg to 9.7 ± 3.9 mm Hg ( P < 0.0001). The complete success rate was 91.6%, 88.4%, 84.7%, 71.6%, 59.7%, and 54.3%, at the first, second, fourth, sixth, eighth, and tenth year, respectively. Follow-up averaged 42.1 ± 28.4 months. Preoperatively, 72 eyes (73.5%) had significant corneal edema versus 11 eyes (11.2%) at the end of the follow-up ( P < 0.0001). Endophthalmitis was encountered in one eye. Myopia was the most common refractive error (80.6%). Data on Snellen VA were available for 53.2% of the patients; 33.3% achieved a VA ≥6/12, 21.2% had mild VI, 9.1% had moderate VI, 21.2% had severe VI, and 15.2% were blind. The failure rate was statistically correlated to the early disease onset (<3 mo) and to preoperative corneal edema ( P = 0.022 and P = 0.037, respectively).

CONCLUSION

Primary CTT seems to be a good procedure in a population with advanced PCG at presentation, problematic follow-up visits, and limited resources.

12-month outcomes of ab interno excisional goniotomy combined with cataract surgery in primary open-angle glaucoma and normal tension glaucoma

PURPOSE

To evaluate the efficacy and safety of excisional goniotomy performed with the Kahook Dual Blade (KDB) combined with cataract surgery in patients with pimary open angle glaucoma (POAG) and Normal Tension Glaucoma (NTG) under topical therapy. Further sub-analysis was performed to compare between 90 and 120 degrees goniotomy.

METHODS

This was a prospective case series of 69 eyes from 69 adults (age 78 ± 5.9 years; male = 27, female = 42). Indications for surgery included insufficient IOP control with topical medication, glaucomatous damage progression under topical therapy and reduction of medication burden. Complete success was defined as IOP lowering below 21 mmHg without the need for topical medication. For NTG patients, complete success was defined as IOP lowering below 17 mmHg without the need for topical medication.

RESULTS

IOP was significantly lowered from 19.7 ± 4.7 to 15.1 ± 2.7 at 2 months, 15.8 ± 2.3 at 6 months and 16.1 ± 3.2 at 12 months (p < 0.05) for POAG and 15.1 ± 2.5 to 14.1 ± 2.4 at 2 months, 14.1 ± 3.1 at 6 months and 13.6 ± 1.8 at 12 months (p > 0.08) for NTG, respectively. Complete success was achieved in 64% of the patients. IOP lowering under 17 mmHg without the need for topical medication was achieved in 60% of the patients at 12 months. In NTG patients (14 eyes) IOP lowering under 17 mmHg without the need for topical medication was achieved in 71%. No significant difference was recorded in terms of IOP lowering at 12 months in-between 90° and 120° of treated trabecular meshwork (p > 0.7). No severe adverse reactions were recorded in this study.

CONCLUSION

One-year results show that KDB combined with cataract surgery is an effective treatment option for glaucoma patients. IOP lowering was successfully achieved in NTG patients with complete success in 70% of the patients. In our study, no significant differences were recorded in-between 90° and 120° of treated trabecular meshwork.

Risk of Neurotoxicity with Multiple General Anaesthetics for Examination Under Anaesthesia in Paediatric Ophthalmology - A Cause for Concern?

Purpose

To evaluate the impact of clinical protocol change via active minimisation on the number of general anaesthetic (GA)/sedation episodes for diagnostic ophthalmic purposes at Children's Health Ireland at Temple Street (CHI-TS), Dublin, Ireland, from 2016 to 2019, inclusive. Change was implemented following published cautionary principles in 2016 by the FDA regarding the potential neurotoxic risk from multiple GA exposure in children.

Methods

Retrospective analysis of electronic operating theatre records was completed using procedure codes "Ophthalmological examination" and "Examination of fundi". Available records for patients undergoing multiple examination under anaesthesia (EUA) procedures were assessed for demographics, indication. Comparison was made regarding overall EUA numbers and breakdown for each year, before and after the new departmental approach. From 2018 onward, a patient-centred, departmental strategy of active minimisation of EUA was adopted, using strategies of "training, technology and patience". A literature review was conducted using online databases.

Results

A total of 450 EUAs were performed over the 4 years investigated. In the former 2 years of the study period, prior to departmental policy change, EUAs represented 32% (304 of 948 total theatre episodes) of the ophthalmic theatre caseload. In the latter 2 years of this study period, this proportion fell to 19% (146 EUAs of 783 theatre episodes). Total theatre case numbers were comparable in both time periods. Eighteen children had multiple EUAs (ie, ≥2 EUAs, mean 6.5, SD 2.9) for life/sight threatening indications, totalling 116 EUAs (25.7%).

Conclusion

A significant reduction in diagnostic EUA volume was accomplished resulting in reduced individual patient risk and increased capacity for surgical interventions. A detailed description of this methodology is included for the purposes of replication at comparable units. EUA will continue to play a crucial role in the management of life/sight threatening conditions but the application of a cautionary principle to reduce EUA, where possible, is appropriate to reduce potential for neurotoxicity.

Pediatric Glaucoma-From Screening, Early Detection to Management

Pediatric glaucoma (PG) covers a rare and heterogeneous group of diseases with variable causes and presentations. Delayed diagnosis of PG could lead to blindness, bringing emotional and psychological burdens to patients' caregivers. Recent genetic studies identified novel causative genes, which may provide new insight into the etiology of PG. More effective screening strategies could be beneficial for timely diagnosis and treatment. New findings on clinical characteristics and the latest examination instruments have provided additional evidence for diagnosing PG. In addition to IOP-lowering therapy, managing concomitant amblyopia and other associated ocular pathologies is essential to achieve a better visual outcome. Surgical treatment is usually required although medication is often used before surgery. These include angle surgeries, filtering surgeries, minimally invasive glaucoma surgeries, cyclophotocoagulation, and deep sclerectomy. Several advanced surgical therapies have been developed to increase success rates and decrease postoperative complications. Here, we review the classification and diagnosis, etiology, screening, clinical characteristics, examinations, and management of PG.

Outcomes of Non-Penetrating Deep Sclerectomy for Primary Congenital Glaucoma Performed by Experienced versus Trainee Surgeons: A Cohort Study

Purpose

To compare the outcomes of non-penetrating deep sclerectomy (NPDS) for primary congenital glaucoma (PCG) performed by experienced vs trainee surgeons.

Patients and Methods

This retrospective cohort study was conducted in 2022 in Saudi Arabia. Consultants (Gr-1) and trainee pediatric ophthalmologists (Gr-2) performed NPDS on pediatric patients with PCG. Success was defined as an intraocular pressure (IOP) less than 21 mmHg at 6 months after surgery. Complications, glaucoma medications, and additional procedures were also observed in the two groups.

Results

Gr-1 and Gr-2 operated on 14 and 39 eyes with PCG, respectively. The absolute success rates were 90.9% (95% confidence interval [CI]: 73.9, 100) in Gr-1 and 96.7% (95% CI: 90.2, 100) in Gr-2 (odds Ratio=1.1; 95% CI: 0.87, 1.3; P=0.54). Survival analysis suggested that the failure rate in the first 6 months after NPDS was not significantly different between the two groups (hazard ratio=1.45; 95% CI: 0.13, 16.0; P=0.767). The complications included hypotony (2 cases), vitreous hemorrhage (1 case), and total flap penetration (1 case). Only one eye in Gr-2 needed glaucoma medication after surgery. There was no significant difference in the success rates of one surgeon before and after training (P=0.43). The age (P=0.59) and sex (P=0.77) of patients, type of surgeon (P=0.94), and preoperative IOP (P=0.59) were not significant predictors of a stable IOP at 6 months after NPDS.

Conclusion

At 6 months after NPDS surgery performed by experienced and trainee pediatric ophthalmologists, the outcomes (stabilization of IOP) were similar between the two groups.

Screening, Diagnosis, and Treatment of Pediatric Ocular Diseases

Vision is an important aspect of a child's quality of life and intellectual, social, and emotional development. Disruptions to vision during infancy and early childhood can cause lifelong vision impairment or blindness. However, early identification and treatment of eye disease can prevent loss of sight and its consequent long-term effects. Therefore, screening guidelines exist to guide physicians in detecting the most common threats to sight in the different stages of infancy and childhood. This review describes common causes of pediatric vision impairment, the recommended screening guidelines for diagnosing them, and current treatment modalities.

Ocular Manifestations in Patients with Sensorineural Hearing Loss

Identification of ocular manifestations in patients with sensorineural hearing loss (SNHL) can have a large impact on the outcome and treatment of pediatric patients. Due to the common co-incidence of ocular manifestations and SNHL in children, both ophthalmologic and hearing loss screening and routine examinations must be conducted to minimize adverse outcomes and worsening of pathology. Early evaluation and diagnosis is imperative for intervention and further development of the patient. Co-incidence requires a thorough evaluation that includes a comprehensive history, examination, and diagnostic testing. In this article, a literature review was conducted to analyze the presentations of various diseases and syndromes, such as Alport Syndrome, Waardenburg Syndrome, Norrie Disease, Usher Disease, Stickler Syndrome, Marfan Syndrome, Congenital Rubella, and Hereditary Optic Neuropathies. We divided the various ocular pathologies into anterior and posterior segment presentations and associated systemic findings for better understanding. Additionally, this review aims to include an update on the management of patients with both ocular and hearing loss manifestations.

Gonioscopy-assisted transluminal trabeculotomy for congenital glaucoma secondary to Klippel-Trenaunay-Weber Syndrome: A case report

Purpose

To describe the case of a 9-year-old boy with congenital glaucoma secondary to Klippel - Trenaunay - Weber Syndrome (KTW) with a history of trabeculotomy in both eyes (BE) and further trabeculectomy in the left eye (LE) presented with high intraocular pressure (IOP) and progression in the LE despite maximum tolerated medical therapy.

Observations

GATT surgery was performed firstly in the LE, followed by the right eye (RE) two months apart since the IOP in the RE started to increase later on. First post-operative day the IOP was under 15 mmHg. In the last visit, 6 months after the first surgery, IOPs were 10 and 11 mmHg RE and LE, on one fixed combination; slit lamp examinations were normal with wide open angles and a good view of the Schlemm's Canal (SC) posterior wall.

Conclusions and Importance

GATT surgery can be done after failed incisional surgery in children with glaucoma secondary to KTW syndrome.

Changes in Corneal Thickness in Congenital Glaucoma, Using Anterior Segment Optical Coherence Tomography

Purpose: We examined corneal thickness, particularly morphological changes in the limbus, as the intraocular pressure increased in patients with congenital glaucoma.Methods: We retrospectively studied 31 children (47 eyes) with congenital glaucoma and 12 controls (12 eyes). We used anterior segment tomography to measure corneal thicknesses at the center, the midpoint of the 2-5 mm pericentral zone, the corneo-limbal junction, and the scleral spurs on the nasal and temporal sides. The peripheral central corneal thickness ratios were calculated and analyzed using a generalized estimation equation.Results: The cornea was significantly thinner in the glaucoma than in the control group. The difference was more prominent in the periphery than the center. Associated with such peripheral thinning, the corneal thickness ratios at the corneal-limbal junction and the center differed significantly between the two groups.Conclusions: In congenital glaucoma patients, the cornea is generally thinner than that of the controls, particularly at the corneo-limbal junction, suggesting that the limbus is biomechanically susceptible to deformation by intraocular pressure.

Acute hydrops as an atypical presentation of primary congenital glaucoma

Primary congenital glaucoma (PCG) is a disease of childhood characterized by elevated intraocular pressure (IOP) that causes stretching of the eye's outer coats, namely sclera and cornea. This results in the elongation of the eyeball and expansion of the horizontal corneal diameter giving the appearance of a buphthalmos eye. Aggressive disease with high IOP readings causes excessive mechanical stretching that may be poorly tolerated by the corneal Descemet's membrane, leading to large breaks in it with subsequent corneal edema due to sudden influx of the aqueous humor into the exposed stroma, resulting in acute corneal hydrops. While acute hydrops is a potential sequel of PCG, it is considered one of its rare presentations. We present two cases who presented to our hospital with acute hydrops secondary to PCG. Both patients were managed surgically where the first patient underwent combined trabeculotomy-trabeculectomy with mitomycin C, while the second patient underwent deep sclerectomy with mitomycin C. The surgical procedures effectively controlled the IOP and aided in clearing corneal edema in both patients. Early diagnosis and timely surgical intervention are of paramount importance to improve visual outcomes, enhance ocular maturation, and prevent potential irreversible vision loss, especially in this young-age group of patients that are prone to amblyopia.

Trabeculotomy Versus Combined Trabeculotomy-Trabeculectomy for Management of Primary Congenital Glaucoma

PRCIS

Trabeculotomy (T) alone is as safe and effective as combined trabeculotomy-trabeculectomy (TT) in patients with primary congenital glaucoma (PCG) and requires significantly fewer examinations under anesthesia in the postoperative period.

PURPOSE

The purpose of this study was to compare the outcomes of T and combined TT as the initial surgical procedure for patients with PCG.

METHODS

In this retrospective study, medical records of patients who had undergone T or TT as the initial procedure for PCG were reviewed. The primary outcome measure was a surgical success, defined as 5≤ intraocular pressure (IOP) ≤21 mm Hg, IOP reduction of at least 20% with no need for further glaucoma surgery. Secondary outcome measures were the number of glaucoma medications and complications.

RESULTS

A total of 134 eyes from 134 patients with a mean follow-up of 8±6.6 years were included consisting of 106 and 28 eyes, which had undergone T and TT, respectively. Success rates were comparable with both surgical procedures at 1, 2, 3, 4, and 5 years with no statistically significant difference. IOP was significantly decreased from 27.5±4.2 mm Hg preoperatively to 15.62±3.4 mm Hg at the 5-year follow-up visit in the T group and from 25.3±6.5 to 17.1±3.2 mm Hg in the TT group (P=0.1) there was no significant difference between the 2 groups in the number of glaucoma medications (P=0.2). Patients in the T group required significantly fewer examinations under anesthesia than the TT group (7.3±4.4 vs. 10.1±3.9, P=0.04).

CONCLUSION

Trabeculotomy alone seems as effective as combined trabeculotomy-trabeculectomy and may significantly reduce exposure to anesthesia in primary congenital glaucoma patients.

Geographical Variability in CYP1B1 Mutations in Primary Congenital Glaucoma

Primary congenital glaucoma (PCG) is a rare type of glaucoma that is inherited in an autosomal recessive manner. PCG can lead to blindness if not detected early in children aged 3 or younger. PCG varies in presentation among various populations, where disease presentation and disease severity vary by mutation. The most common gene implicated in PCG is cytochrome p450 1B1 (CYP1B1). Here, we sought to review the literature for mutations in CYP1B1 and their presentation among different populations. Areas of interest include recent findings on disease presentation and potential implications on our understanding of PCG pathophysiology.

Factors affecting the surgical success of trabeculectomy performed as the first surgery in primary pediatric glaucoma

PURPOSE

To present the outcomes and factors affecting the success of trabeculectomy performed as the first surgery in primary pediatric glaucoma.

METHODS

Pediatric patients with primary glaucoma who underwent trabeculectomy as the first surgery were retrospectively reviewed. Age, gender, preoperative intraocular pressure (IOP), operation age, axial length, corneal diameter, anterior segment findings, antimetabolite used, complications, and 1-month, 3-months, 1-year, and most recent postoperative findings were recorded. Postoperative IOP with/without medication of 18 mmHg or less was considered successful. Factors that may have affected surgical success were also evaluated using multivariate analysis.

RESULTS

Included in the study were 48 patients, of whom 30 had primary congenital glaucoma and 18 had juvenile glaucoma. The mean preoperative IOP was 36.84 ± 6.30 mmHg, and the mean follow-up time was 7.95 ± 6.93 years. The median operation age value was 100.00 ± 100.83 (median: 60; IQR: 153) months. The postoperative IOP at the 1-month, 3-months, 1-year, and most recent follow-ups were 15.39 ± 6.88, 15.70 ± 7.36, 16.28 ± 7.86, and 17.48 ± 8.44 mmHg, respectively (p = 0.565). While there were no postoperative complications in 24 of the patients (50.0%), the most common complications were choroidal detachment and hypotony. Postoperative complication development was found to be significant as a factor affecting surgical success in the multivariate logistic regression analysis. Surgical success rates for all of the patients were 71.7%, 65.9%, 65.0%, and 61.4% at the 1-month, 3-months, 1-year, and most recent follow-ups, respectively. A significant difference was found between the congenital and juvenile groups in terms of surgical success only at 3 months (p = 0.953, p = 0.042, p = 0.191, p = 0.218; respectively).

DISCUSSION/CONCLUSION

The fact that surgical success was partially higher in the juvenile group confirmed the idea that the results of trabeculectomy will be more favorable in patients of older age and without anterior segment anomalies.

Long-term visual outcomes of primary congenital glaucoma in China

INTRODUCTION

To investigate the long-term visual outcomes and factors associated with vision loss in Chinese patients with primary congenital glaucoma (PCG) after successful intraocular pressure (IOP) control (IOP ≤ 21 mmHg).

METHODS

PCG patients with IOP control who were examined in the glaucoma clinic at Zhongshan Ophthalmic Center from 2019 to 2020 were enrolled. The final visual outcome was evaluated by the best-corrected visual acuity. Univariate and multivariate analyses were used to investigate the associations of visual impairment with potential risk factors. The causes for decreased visual acuity (VA, < 20/50) were also analyzed.

RESULTS

Fifty-nine patients (95 eyes) were included in the cohort, with a mean age of 8.7 years. The mean logMAR VA was 0.62 ±0.64. The VAs of eyes treated for PCG were good (≥20/50) in 56%, fair (20/60 to 20/200) in 30%, and poor (< 20/200) in 14%. The most common cause of decreased VA was amblyopia (64.3%). Multivariate logistic regression analysis showed that undergoing multiple surgeries (OR: 4.86, 95% CI: 1.11-21.16, P=0.035) was significantly associated with visual impairment.

CONCLUSION

The results showed that good VA was attainable in approximately half of PCG eyes under IOP control. Prompt and effective treatment of PCG, management of amblyopia and ocular comorbidities may be potential steps toward achieving good visual outcomes in PCG patients.

Combined nasal goniotomy - temporal trabeculotomy (NGTT) for circumferential angle surgery in primary congenital glaucoma

PURPOSE

To assess the safety and efficacy of combining nasal goniotomy with temporal trabeculotomy in the management of primary congenital glaucoma.

DESIGN

Case series.

METHODS

Fifteen eyes of eleven children (3-12 months old at presentation) were enrolled in this study after the establishment of PCG diagnosis based on the criteria placed by the World Glaucoma Association. Combined nasal goniotomy and temporal trabeculotomy were done on each eye in an attempt to perform almost 360 degrees circumferential angle surgery without disturbing the superior 180 degrees of conjunctiva to preserve it for future filtering glaucoma surgeries.

RESULTS

By first month, average IOP was 10.5 ± 4.3 mmHg with a 65.3% reduction from average pre-operative IOP. Almost the same percentage of reduction was maintained at 3^rd,6^th and 12^th months postoperative visits with average IOP of 11.9 ± 4.65, 11.8 ± 2.77 and 13 ± 2.82 mmHg (60.7%, 61.1% and 57.2% reduction from pre-operative average). According to success rates, complete success has been achieved in all eyes but one (93.3%), with minor complications in 4 out of 15 eyes (26.6%) that did not affect IOP outcome. Nine out of fifteen eyes completed 18 months post-operative follow-up visits with a successfully, maintained target average IOP of 13.3 ± 3.0 mmHg (57.2% reduction). All of the mean IOP readings during post-operative follow-up period were significantly lower when compared to pre-operative IOP (p < 0.0001). Only one eye had persistently elevated IOP of 26 mmHg at 1^st and 3^rd months post-operatively that necessitated a subsequent subscleral trabeculectomy which succeeded in controlling the pressure bringing it down to 15 mmHg on topical medications.

CONCLUSION

Nasal goniotomy - temporal trabeculotomy (NGTT) is the combination of two well established surgeries that exploits the advantages of circumferential angle surgery while sparing the superior conjunctiva completely for future surgeries if needed. This new procedure was safe and effective in lowering IOP by an average of 60% from pre-operative IOP with a sustained effect till 18 months post-operatively. We believe that this surgery might be added to the armentarium of the surgical management of infantile glaucomas with other circumferential angle surgeries.

Early-Onset Glaucoma in egl1 Mice Homozygous for Pitx2 Mutation

Mutations in PITX2 cause Axenfeld–Rieger syndrome, with congenital glaucoma as an ocular feature. The egl1 mouse strain carries a chemically induced Pitx2 mutation and develops early-onset glaucoma. In this study, we characterized the glaucomatous features in egl1 mice. The eyes of egl1 and C57BL/6J control mice were assessed by slit lamp examination, total aqueous humor outflow facility, intraocular pressure (IOP) measurement, pattern electroretinography (PERG) recording, and histologic and immunohistochemistry assessment beginning at 3 weeks and up to 12 months of age. The egl1 mice developed elevated IOP as early as 4 weeks old. The IOP elevation was variable and asymmetric within and between the animals. The aqueous humor outflow facility was significantly reduced in 12-month-old animals. PERG detected a decreased response at 2 weeks after the development of IOP elevation. Retinal ganglion cell (RGC) loss was detected after 8 weeks of IOP elevation. Slit lamp and histologic evaluation revealed corneal opacity, iridocorneal adhesions (anterior synechiae), and ciliary body atrophy in egl1 mice. Immunohistochemistry assessment demonstrated glial cell activation and RGC axonal injury in response to IOP elevation. These results show that the eyes of egl1 mice exhibit anterior segment dysgenesis and early-onset glaucoma. The egl1 mouse strain may represent a useful model for the study of congenital glaucoma.

Progression in pediatric glaucoma: lessons learnt from 8 years' follow-up

Background

Surgical procedures are used as 1 of the main treatment modalities for pediatric glaucoma, even though progression may occur. In this study, we aimed to investigate the risk factors affecting the progression of pediatric glaucoma.

Methods

In this retrospective cohort study, we reviewed the medical records of patients diagnosed with pediatric glaucoma between April 2009 and March 2017. Pediatric glaucoma patients who underwent regular follow-up for at least 1 year were included. Demographics, intraocular pressure (IOP), central corneal thickness (CCT), axial length (AL), cup-to-disc ratio (C/D ratio), corneal diameter, type of glaucoma, age at time of diagnosis, and age at surgery were recorded. Progression was defined as an increase in AL > 2 mm, C/D ratio > 0.2, or corneal diameter > 1 mm during 1 year of follow-up.

Results

Eighty-three eyes from 46 patients were included: 37 eyes (45%) with primary congenital glaucoma (PCG), 46 eyes (55%) with secondary glaucoma, and 27 of these 83 eyes (32.5%) showed progression. Progression was comparable between eyes with PCG and secondary glaucoma (PCG, 22%; secondary glaucoma, 41%; P = 0.152). Age at the time of diagnosis and age at the time of the first surgery were significantly lower in the eyes with progression (P = 0.046 and 0.012, respectively). The mean (standard deviation) of surgeries in progressed versus non-progressed eyes was 1.88 (1.1) versus 1 (0.8) (P = 0.015). The frequency of comorbid systemic disease was significantly higher in patients with glaucoma progression (P = 0.043). The progressed and non-progressed eyes were comparable in terms of other demographic characteristics and ocular parameters (all P > 0.05).

Conclusions

Pediatric glaucoma patients who were younger at the time of diagnosis and the first glaucoma surgery and those with comorbid systemic disease are at higher risk of glaucoma progression. These findings are useful for clinicians when counseling parents of children with pediatric glaucoma about disease outcomes. However, future prospective studies with larger sample sizes and longer follow-up periods are needed to confirm our findings.

Visual Evoked Potentials in Operated Primary Congenital Glaucoma: A Cross-Sectional Comparative Study

Background

To evaluate the VEP parameters in operated controlled primary congenital glaucoma (PCG) eyes and compare them to normal age similar children eyes.

Methods

A cross-sectional comparative study conducted on 34 (19 right) eyes of 26 (19 males) children operated for PCG and 30 (17 right) eyes of 22 (12 males) age similar control children in a university-based practice. All study participants were subjected to a standard protocol of examination and electrophysiological testing (single flash VEP response, light adapted, pupils not dilated), reporting on the P2 implicit time, N1-P1 and N2-P2 (amplitude).

Results

The mean±SD of the age of the study children and controls was 43.22±33.2 and 55.68±35.2 months respectively (p=0.217). The mean±SD IOP and cup/disc ratio of the study children were 18.4±5.2 and 5.2±3.3mmHg and 0.7±0.2 and 0.3±0.3 at presentation and at testing, respectively. The VEP testing was conducted after 21.5±21.3 months of surgery for PCG. There was no statistically significant differences in P2, N1-P1 and N2-P2 between patients and controls (p=0.941, 0.916,0.945, respectively). There was no statistically significant correlation between most of the clinical characteristics of the study eyes and any of the studied VEP parameters.

Conclusion

Operated controlled PCG eyes have VEP parameters that match their normal fellow children.

Kahook Dual Blade Ab-interno Trabeculectomy Compared With Conventional Goniotomy in the Treatment of Primary Congenital Glaucoma: 1-Year Results

INTRODUCTION

Kahook dual blade (KDB) removes a strip of the trabecular meshwork from the angle, which may make it superior to simple goniotomy in treating the angle anomaly in primary congenital glaucoma (PCG). This prospective study compares KDB ab-interno trabeculectomy to conventional goniotomy in PCG.

METHODS

Forty-two eyes of 29 patients with PCG underwent ab-interno trabeculectomy using a KDB or conventional goniotomy using a 25-G irrigating needle, targeting 100 to 120 degrees of the nasal iridocorneal angle. Patients were seen at 1, 3, 6, and 12 months postoperatively. Success was defined as intraocular pressure (IOP) ≤21 mm Hg at 1-year follow-up visit, with no evidence of glaucoma progression.

RESULTS

The KDB group included 21 eyes of patients with a median age of 6 months (interquartile range: 4 to 8.5 mo) and the goniotomy group included 21 eyes of patients with a median age of 5 months (interquartile range: 3 to 9.5 mo). There was a significant reduction in IOP in both groups at all follow-up visits. The reduction in the number of glaucoma medications was significant at 1, 3, and 6 months postoperatively in the KDB group, and at 1 month in the goniotomy group. There was no significant difference in IOP or glaucoma medications between both groups at any follow-up visit. Success was achieved in 12 eyes (57.1%) in each group, with no eyes developing any serious complications.

CONCLUSION

One-year results show that KDB ab-interno trabeculectomy is at least as effective as goniotomy in the treatment of PCG. Eyes with bilateral glaucoma had a tendency to fail both procedures.

Mutational analysis of CYP1B1 gene in Iranian pedigrees with glaucoma reveals known and novel mutations

PURPOSE

Primary congenital glaucoma (PCG) (OMIM#231,300) can be caused by pathogenic sequence variations in CYP1B1, LTBP2, MYOC and PXDN genes. The purpose of this study was to investigate mutations in the CYP1B1 gene in families affected with primary congenital glaucoma (PCG) using linkage analysis and Sanger sequencing.

METHODS

A total number of four families with nine affected PCG patients during six months were included in this study. The mutations were identified by homozygosity mapping to find the linked loci and then direct sequencing of all coding exons, the exon-intron boundaries and the 5' untranslated region of CYP1B1 using genomic DNA obtained from affected family members and their parents. Moreover, bioinformatic tools were applied to study mutation effect on protein structure and function.

RESULTS

A total of four mutations were identified, and three of these were novel. Two were missense mutations: One was truncating mutation, and the other was an in-frame deletion. Mutations in CYP1B1 could fully explain the PCG phenotype in all of the patients. Also, the bioinformatic study of the mutations showed the structure of the protein is affected, and it is well conserved among similar species.

CONCLUSION

In this study, we identified 4 CYP1B1 mutations, 3 of which were novel. In silico analysis of identified mutations confirmed their molecular pathogenicity. A similar analysis will help understand the biological role of CYP1B1 and the effect of mutations on the regulatory and enzymatic functions of CYP1B1 that result in PCG.

CLINICAL TRIALS REGISTRATION

Not relevant.

Lens in Primary Congenital Glaucoma Eyes Treated by Combined Angle and Filtering Surgery

PURPOSE

To report on the changes in the natural crystalline lens in primary congenital glaucoma (PCG) eyes that had undergone previous combined angle-filtering surgery with antimetabolites.

SETTINGS

The pediatric ophthalmology unit of the ophthalmology department of Alexandria Main University Hospital.

DESIGN

A retrospective chart review.

METHODS

A retrospective chart review of patients presenting with and operated (by combined angle-filtering surgery with antimetabolites) for PCG in the period from 2005 to 2018. Any lens pathology was noted as well as the management and the outcome.

RESULTS

The records of 422 children (613 eyes) were reviewed. Lens pathology was noted in 54 (8.8%) eyes. Abnormalities in lens clarity (cataract) were detected in 31 (56%) eyes, and abnormalities in lens position (subluxation) were detected in 24 (44%) eyes. Management options included observation (in 28 eyes), lensectomy for aphakia (in 14 eyes), lensectomy with in the bag intraocular lens (IOL) implantation (in 11 eyes), and lensectomy with iris-fixated IOL (in 1 eye). Elevation of intraocular pressure (IOP) occurred in only 4 eyes (of 26 operated eyes, 15.3%) after lens extraction.

CONCLUSIONS

Changes in the natural crystalline lens clarity and/or position occurred in 8.8% (54 of 613) of PCG eyes operated by combined angle-filtering surgery with antimetabolites. Lens extraction was a relatively safe procedure with only 15% (4 of 26) of eyes suffering an elevation of IOP after lens extraction.

Ab Interno Goniotomy Combined with Ab Externo Trabeculotomy in Advanced Primary Congenital Glaucoma Patients: 2-Year Follow-Up

Introduction

Primary congenital glaucoma (PCG) is a challenging disease that needs to be surgically managed with more innovative methods. Conventional incisional surgery, such as goniotomy and trabeculotomy, has a primary high success rate, but does not seem to be a very effective treatment in advanced stages.

Design

A prospective clinical case study.

Purpose

To qualify the outcome, in terms of success rate, of goniotomy combined with trabeculotomy as a surgical option to treat eyes affected by PCG with a corneal diameter larger than 14 mm.

Patients and Methods

This study included 50 eyes of 50 patients diagnosed with PCG with corneal diameter larger than 14 mm who underwent ab interno goniotomy combined with ab externo trabeculotomy. Intraocular pressure (IOP) was measured preoperatively and 24 months postoperatively. A statistical analysis was performed to detect correlations between the success rate and corneal diameter, preoperative IOP, age of onset, axial length, and consanguinity. The main outcome was reduction in IOP; secondary outcomes were factors affecting the success rate, complications, and the need for additional surgical intervention to control IOP.

Results

The mean age of the patients was 18.86±9.94 months. Males made up 52% of cases and females 48% of cases. Positive consanguinity was present in 38% of cases. Axial length ranged between 20 and 22 mm, with a mean of 20.98±0.8 mm. Mean preoperative IOP was 29.56±3.36 mmHg, which decreased postoperatively to 12.6±2.5, 14.1±3.2, 16.8±5.5, 14.4±2.3, 14.3±1.6, 14.3±1.6, 14.3±1.6, 14.3±1.7, and 14.3±1.7 mmHg at 1, 3, 6, 9, 12, 15, 18, 21, and 24 months respectively (p˂0.001). Use of medical treatment was decreased from 2.7±0.4 preoperatively to 1.4±0.7 postoperatively (p˂0.001). Hyphema was the only complication that appeared, occurring in 47% of cases. The success rate was 94%. Complete success (IOP <21 mmHg without treatment) was achieved in 70% of cases, 24% were considered a qualified success (IOP <21 mmHg with treatment), while failure was documented in 6% of cases (IOP >21 mmHg with treatment). The success rate was significantly related to preoperative IOP, corneal diameter, axial length, consanguinity, and age of onset (p˂0.001). All cases were followed for 24 months.

Conclusion

Ab interno goniotomy combined with ab externo trabeculotomy improves the success rate of buphthalmos surgery. A significant correlation was detected between success rate and preoperative IOP, corneal diameter, axial length, consanguinity, and age of onset.

The Epidemiological and Clinical Findings from the Latvian Registry of Primary Congenital Glaucoma and Evaluation of Prognostic Factors

Background and objectives: primary congenital glaucoma (PCG) is a rare, potentially blinding disease that affects children worldwide. The aim of the study was to describe the epidemiological and clinical characteristics, outcomes for newly diagnosed patients with PCG, as well as evaluate the prognostic factors that are related to the outcomes. Materials and Methods: a retrospective cohort study was conducted at a tertiary referral centre among patients diagnosed with PCG. Evaluation of the clinical data was performed preoperatively at three, six, and 12 months after the surgery and at the last follow-up. Results: during the 15 years of follow-ups, 24 eyes of 18 patients were diagnosed with PCG. Unilateral and bilateral PCG constituted 50% of cases each. A slight male predominance was observed (55.6% vs. 44.4%), with a relative risk of 1.3. The incidence of PCG was 1:19,033 live births. The mean age of the patients at the time of diagnosis was 10.1 ± 10.0 months, with a diagnostic delay of 2.0 ± 1.9 months. Furthermore, 75% of patients indicated an enlargement of an eyeball, followed by excessive tearing (58.3%) and corneal opacity (41.7%). After 85.9 ± 51.2 months, the mean intraocular pressure (IOP) value was 14.6 ± 4.9 mmHg. Surgical treatment provided sufficient IOP control in 75% of PCG cases at the last follow-up visit. The only prognostic factor that was related to the outcome of IOP control that was statistically significant was axial length at the time of diagnosis. Conclusions: the incidence of PCG in Latvia was 5.3 patients per 100,000 live births. PCG was more common among males than females with a relative risk of 1.3. The enlargement of an eyeball was the leading clinical sign.

Surgical Outcomes of Microcatheter-assisted Trabeculotomy as a Secondary Procedure in Patients with Primary Congenital Glaucoma

PURPOSE

To investigate the efficacy and safety of illuminated microcatheter-assisted trabeculotomy as a secondary procedure in patients with primary congenital glaucoma (PCG).

METHODS

This retrospective case series included patients with PCG who underwent trabeculotomy using an illuminated microcatheter with the intent of catheterizing the full circumference of Schlemm's canal in a single procedure. Success was defined as intraocular pressure (IOP) ≤21 mmHg, with or without the use of glaucoma medications. Clinical examination data were collected for up to 36 months postoperatively.

RESULTS

Surgery was performed on 16 eyes of 16 patients. The mean patient age was 75.1 ± 69.4 months (range: 4.0-216.0 months). Complete catheterization was achieved in 11 of the 16 eyes (69%), whereas partial catheterization was achieved in five of the 16 eyes (31%). All eyes had previously undergone surgery for PCG. The mean follow-up duration was 20.3 ± 9.0 months (range, 12.0-36.0 months). IOP was reduced from a mean of 31.8 ± 6.6 mmHg preoperatively to 15.6 ± 3.7 mmHg at the final follow-up (P < 0.001). The mean preoperative number of glaucoma medications was 3.9 ± 0.5, which was reduced to 1.1 ± 1.6 at the final follow-up (P = 0.001). Ten (62.5%) of the 16 eyes did not require glaucoma medication by the final follow-up. Early transient postoperative hyphema occurred in six eyes (37.5%). No other complications were noted. All corneas were clear at the final follow-up.

CONCLUSION

Ab externo circumferential trabeculotomy using an illuminated microcatheter may be safe and effective as a secondary surgical option for children with PCG after unsuccessful glaucoma surgery.

The Long-term Visual Outcomes of Primary Congenital Glaucoma

Purpose

To evaluate the long-term visual outcomes of ab externo trabeculotomy for primary congenital glaucoma (PCG) at a single pediatric ophthalmology center.

Methods

In this retrospective single-center case series, data from 63 eyes of 40 patients who underwent ab externo trabeculotomy between September 2006 and June 2018 were included. The data were analyzed for best corrected visual acuity (BCVA), stereopsis, and surgical success. Kaplan–Meier analysis was performed using the surgical success criteria defined as intraocular pressure (IOP) ≤ 21 mmHg and ≥ 20% below baseline without the need for additional glaucoma surgery.

Results

BCVA at the time of diagnosis was 0.37 ± 0.48 logMAR, which changed to 0.51 ± 0.56 logMAR at the final follow-up (P = 0.08). Twenty-five percent of patients had BCVA equal to or better than 20/40 at the final visit. The mean refraction at baseline was –4.78 ± 5.87 diopters, which changed to less myopic refraction of –2.90 ± 3.83 diopters at the final visit. Optical correction was prescribed in 66% of eyes at the final visit. The average final stereopsis was 395.33 sec of arc. The linear regression model showed a significant association between the surgery success rate and final BCVA as well as stereoacuity (P-values: 0.04 and 0.03, respectively). Intraocular pressure (IOP) decreased significantly from 29.79 ± 7.67 mmHg at baseline to 16.13 ± 3.41 mmHg at the final follow-up (P = 0.001).

Conclusion

Patients with PCG can achieve an acceptable visual acuity and stereoacuity, particularly in cases of timely intervention and close follow-up.

A Mitomycin C-Sparing Novel Technique for Subscleral Trabeculectomy in Primary Congenital Glaucoma

Purpose

To evaluate the safety and efficacy of a novel modified subscleral trabeculectomy technique in management of primary congenital glaucoma.

Methods

This study included 25 infants diagnosed of having bilateral primary congenital glaucoma. For each patient, one eye was assigned to undergo subscleral trabeculectomy with trimming of the edges of the scleral bed (group I), while the contralateral eye underwent subscleral trabeculectomy with application of mitomycin C (0.4 mg/ml for 3 min) (group II). All the patients were followed up for a period of 14 ± 3 months (range 13-22 months).

Results

25 eyes were included in each group. Patients' mean age was 2.5 ± 0.5 months (range 1.8-6.5 months). The mean preoperative intraocular pressure was 31 ± 4.9 mmHg and 32.1 ± 4.0 mmHg in group I and II, respectively. The mean postoperative intraocular pressure was 9.0 ± 1.0, 11.0 ± 3.2, 12.5 ± 0.9, 13.0 ± 2.9, and 15.5 ± 1.5 mm Hg in group I and was 10.3 ± 1.2, 12.0 ± 2.5, 13.5 ± 1.7, 15.0 ± 1.5, and 17.1 ± 2.8 mm Hg in group II at the first week and 1, 3, 6, and 12 months, respectively. There was no statistically significant difference between the mean intraocular pressure values recorded at both groups preoperatively and at each follow-up visit. Failure necessitating further surgical interventions was recorded in 4 eyes (16%) in group I as compared to 3 eyes (12%) in group II (P > 0.05). Postoperative complications included mild hyphema, which occurred in one eye (4%) in group I and 2 eyes (8%) in group II, and shallow anterior chamber in 3 eyes (12%) in group I and in 2 eyes (8%) in group II. One eye (4%) in group I developed drawn-up pupil. Choroidal effusion developed in one eye (4%) at each group.

Conclusion

Trimming the edges of the scleral bed adjacent to the sclera flap is a safe and effective surgical step which can be added to the subscleral trabeculectomy procedure to effectively control the intraocular pressure in patients with primary congenital glaucoma, sparing them the hazards associated with mitomycin C application.

Corneal dystrophies

Corneal dystrophies are broadly defined as inherited disorders that affect any layer of the cornea and are usually progressive, bilateral conditions that do not have systemic effects. The 2015 International Classification of Corneal Dystrophies classifies corneal dystrophies into four classes: epithelial and subepithelial dystrophies, epithelial-stromal TGFBI dystrophies, stromal dystrophies and endothelial dystrophies. Whereas some corneal dystrophies may result in few or mild symptoms and morbidity throughout a patient's lifetime, others may progress and eventually result in substantial visual and ocular disturbances that require medical or surgical intervention. Corneal transplantation, either with full-thickness or partial-thickness donor tissue, may be indicated for patients with advanced corneal dystrophies. Although corneal transplantation techniques have improved considerably over the past two decades, these surgeries are still associated with postoperative risks of disease recurrence, graft failure and other complications that may result in blindness. In addition, a global shortage of cadaveric corneal graft tissue critically limits accessibility to corneal transplantation in some parts of the world. Ongoing advances in gene therapy, regenerative therapy and cell augmentation therapy may eventually result in the development of alternative, novel treatments for corneal dystrophies, which may substantially improve the quality of life of patients with these disorders.

Congenital Refractory Glaucoma: A New Ophthalmic Association of Kabuki Syndrome and its Management With Glaucoma Drainage Devices

INTRODUCTION

Kabuki syndrome (KS) is a rare congenital and polymalformative condition, traditionally associated with mental retardation, unusual facial features, and skeletal abnormalities. We hereby describe a case of bilateral congenital glaucoma associated with MLL2-mutation KS. To the best of our knowledge, this is the first association of KS with congenital glaucoma.

CASE REPORT

The patient was a 3-year-old male of North African ethnicity diagnosed with KS and bilateral congenital glaucoma at the age of 3 months and the first child of a nonconsanguineous healthy couple, with no known genetic conditions within the family. The patient was referred to our tertiary glaucoma center with uncontrollable intraocular pressures between 50 and 60 mm Hg in both eyes. Past ophthalmic history included bilateral trabeculectomies and right retinal detachment with phthisis bulbi. We performed left lensectomy combined with Baerveldt tube insertion in the vitreous cavity, revealing extensive posterior synechiae. Postoperatively, he developed intense inflammation with fibrin and vitreous strand formation, requiring subsequent surgeries and subconjunctival injections of betamethasone. Despite these complications, IOP stabilized between 3 and 6 mm Hg.

DISCUSSION

This case confirms congenital glaucoma as a rare association of KS, and highlights the potential high-risk nature of such cases. In our opinion, the presence of high levels of inflammation perioperatively and postoperatively is an indication for primary glaucoma drainage device surgery given the high risk of bleb scarring resulting in recurrent surgical revisions. In view of these observations, we also advocate the use of intensive postoperative anti-inflammatory therapy.

Gonioscopy-assisted transluminal trabeculotomy using an illuminated catheter for infantile primary congenital glaucoma. Case series

Purpose

To describe our experience of Gonioscopy-Assisted Transluminal Trabeculotomy (GATT) in four eyes with infantile primary congenital glaucoma (PCG).

Observations

We report the first two GATT procedures performed in six-month-old infants with PCG. We also report the same procedure in two eyes of a two-year-old boy with PCG who had previous goniotomies with subsequent peripheral anterior synechiae formation. In all four eyes, the IOP remained under 20 mmHg at years three and four postoperatively, without glaucoma medication or conjunctival surgery.

Conclusions and importance

Our cases confirm that GATT is an alternative to traditional ab externo glaucoma surgery in PCG and can be successfully performed within the first months of life, or in infants with failed or partially functioning goniotomies, avoiding the need for invasive conjunctival or scleral surgery.

Severity of visual field defects in primary congenital glaucoma and their risk factors

PURPOSE

The primary objective of the study was to assess the frequency and severity of visual field defects (VFD) in primary congenital glaucoma (PCG). The secondary objective was to ascertain any associated risk factors.

METHODS

An ambispective review of patients with PCG on follow-up with a 'target' intraocular pressure (IOP) of ≤ 15 mmHg. Age, sex, laterality, duration of follow-up, baseline IOP, baseline cup-disc ratio (CDR), central corneal thickness (CCT), age during filtering surgery, second surgery if any, yearly IOP, glaucoma medications and best corrected visual acuity from 2013 (year 1) to the final review and final CDR were noted down. Children ≥ 5 years of age with best corrected visual acuity ≥ 6/60 were subjected to manual kinetic Goldmann perimetry, and visual field defects (VFD) were identified.

RESULTS

Seventy-one of 90 eyes completed a reliable kinetic perimetry. The mean age of children was 12.34 ± 4.86 years, and the mean follow-up duration was 10.77 ± 4.69 years. Baseline IOP and CDR were 29.07 ± 8.83 mmHg and 0.66 ± 0.22, respectively. 86.67% of eyes underwent a trabeculotomy + trabeculectomy with mitomycin-C. Thirty-one eyes (34.44%) required a second surgery, 25 of which were bleb revisions and 3 trabeculectomies. Mean IOP and CDR during last visit were 10.23 ± 2.76 mmHg and 0.52 ± 0.25, p < 0.001 as compared with baseline. On Goldmann perimetry, 19 eyes, 26.76%, had defects, arcuate scotoma being most frequent. On the Fisher exact test, a baseline/final CDR > 0.8, undergoing just a trabeculectomy with MMC, needing ≥ 2 glaucoma medications on review or a repeat trabeculectomy was associated with greater severity of VFD. On univariate logistic regression, eyes that needed a bleb revision [OR, 95% CI 9.75 (2.66-35.67), p = 0.001], a repeat trabeculectomy with mitomycin-C [OR (CI) 18 (1.31-245.58), p = 0.03] and final CDR of > 0.8 [OR (CI) 23.1 (3.7-144.21), p = 0.001] were associated with VFD. On multivariable regression analysis, female sex [OR (CI) 18 (2.01-161.04), p = 0.01] was identified as the single most important risk factor for development of a VFD.

CONCLUSION

At a 'target' IOP of ≤ 15 mmHg, 26.76% of PCG eyes manifested a VFD over 10 years. Baseline and/or final CDR > 0.8, necessity for ≥2 medications or a repeat glaucoma surgery, and female sex were identified as risk factors for development and greater severity of glaucomatous VFD.

Trabeculotomy versus combined trabeculotomy-trabeculectomy for primary congenital glaucoma: study protocol of a randomised controlled trial

INTRODUCTION

Trabeculotomy and combined trabeculotomy-trabeculectomy (CTT) are major surgical options for primary congenital glaucoma (PCG). However, it is unclear which of these two surgical procedures should be recommended as the optimum first-line treatment for PCG. This trial aims to determine whether the outcomes of trabeculotomy are non-inferior to those of CTT in moderate PCG with a horizontal corneal diameter (HCD) of 12-14 mm.

METHODS AND ANALYSIS

This is a 3-year, non-inferiority, prospective, randomised controlled trial. We plan to recruite 248 participants (aged ≤3 years) with PCG with an HCD of 12-14 mm from the Department of Glaucoma, Zhongshan Ophthalmic Center, Guangzhou, China. One eye per participant will be randomly (1:1) assigned to receive trabeculotomy or CTT. The primary outcome is the 3-year postoperative success rate in lowering intraocular pressure (IOP), and the secondary clinical outcomes will include IOP reduction, visual acuity, HCD, central corneal thickness, axial length, cup-disc ratio, refractive error and postoperative complications. Data will be analysed by the intention-to-treat principle.

ETHICAL APPROVAL AND DISSEMINATION

The study protocol has been approved by the ethics committee of Zhongshan Ophthalmic Center (2014MEKY023) and the '5010 Plan' evaluation committee at Sun Yat-Sen University, Guangzhou, China. The results will be disseminated in international academic meetings and published in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

Chinese Clinical Trial Registry, ChiCTR-IOR-14005588; Date registered: 20 November 2014.

Contemporary management of refractory pediatric glaucoma

PURPOSE OF REVIEW

The management of pediatric glaucoma poses a unique challenge in terms of maintaining lifelong vision and combating an aggressive scarring response from surgery. Contemporary literature regarding the surgical management of children with pediatric glaucoma who fail, or are at a high risk of failure, from conventional surgery is limited. The aim of this review is to highlight recent developments in relation to the current opinion regarding the management of children with refractory pediatric glaucoma.

RECENT FINDINGS

Some studies have reported impressive success rates with circumferential trabeculotomy, even in eyes with previous failed surgery. Early results of deep sclerectomy in populations which may not respond well to conventional angle surgery are encouraging but data is limited for the pediatric age group. In compliant patients in whom multiple postoperative examinations under anesthesia are possible, trabeculectomy remains an effective procedure. Multiple recent studies have demonstrated that glaucoma drainage device (GDD) surgery is associated with 5-year success rates of over 70% in primary childhood glaucomas.

SUMMARY

Glaucoma drainage device surgery is likely to remain a mainstay of surgical management for refractory glaucoma in older children. More prospective data are needed on the success of circumferential trabeculotomy, deep sclerectomy and micropulse laser in pediatric eyes with previous failed surgery. VIDEO ABSTRACT: http://links.lww.com/COOP/A34.

Mutational analysis of the CYP1B1 gene in Pakistani primary congenital glaucoma patients: Identification of four known and a novel causative variant at the 3' splice acceptor site of intron 2

Primary congenital glaucoma (PCG) causes blindness in early age. It has an autosomal recessive pattern of inheritance, hence is more prevalent in populations with frequent consanguineous marriages that occur in the Pakistani population. Mutations in the CYP1B1 gene are commonly associated with PCG. The aim of the present study was to identify genetic mutations in the CYP1B1 gene in PCG cases belonging to 38 Pakistani families. DNA was extracted using blood samples collected from all enrolled patients, their available unaffected family members and controls. Direct sequencing of the CYP1B1 gene revealed a novel 3' splice acceptor site causative variant segregating in an autosomal recessive manner in a large consanguineous family with four PCG-affected individuals. The novel variant was not detected in 93 ethnically matched controls. Furthermore, four already reported mutations, including p.G61E, p.R355X, p.R368H, and p.R390H were also detected in patients belonging to nine different families. All identified causative variants were evaluated by computational programs, that is, SIFT, PolyPhen-2, and MutationTaster. Pathogenicity of the novel splice site variant identified in this study was analyzed by Human Splicing Finder and MaxEntScan. Ten out of 38 families with PCG had the disease due to CYP1B1 mutations, suggesting CYP1B1 was contributing to PCG in these Pakistani patients. Identification of this novel 3' splice acceptor site variant in intron 2 is the first report for the CYP1B1 gene contributing to genetic heterogeneity of disease.

Long-term surgical outcomes of ab externo trabeculotomy in the management of primary congenital glaucoma

PURPOSE

To analyze the long-term results of ab externo trabeculotomy with a Harms trabeculotome at a single, tertiary care pediatric hospital.

METHODS

The medical records of pediatric patients operated on between September 2006 and June 2018 were reviewed retrospectively. Kaplan-Meier analysis was performed, with success defined as postoperative intraocular pressure (IOP) of ≤21 mm Hg, >20% reduction from preoperative IOP, and no need for further glaucoma surgery. Risk factors for failure were identified using Cox proportional hazards ratio.

RESULTS

A total of 63 eyes of 40 patients were included. The cumulative probability of success rate was 83% at 3 months, 76% at 6, 73% at 12, 72% at 18, and 65% at final visit. Presentation within 3 months of life was associated with a less favorable outcome. Thirty-five eyes (56%) underwent repeat trabeculotomy to treat a different area of the trabecular meshwork because of inadequately controlled IOP after the first session. Of those who needed another session of trabeculotomy, the final success rate was 60.2%. IOP significantly decreased from 29.79 ± 7.67 mm Hg at baseline to 16.13 ± 3.41 mm Hg by final follow-up (P = 0.001). Patients were followed for an average of 85.74 ± 32.95 months. IOP and success rates remained stable 18 months after surgery.

CONCLUSIONS

In our patient cohort, ab externo trabeculotomy was associated with good long-term results. More extensive trabeculotomy (ie, more than one procedure) was associated with better long-term success rates.

A Multidisciplinary Consensus for Clinical Care and Research Needs for Sturge-Weber Syndrome

BACKGROUND

Sturge-Weber syndrome is a neurocutaneous disorder associated with port-wine birthmark, leptomeningeal capillary malformations, and glaucoma. It is associated with an unpredictable clinical course. Because of its rarity and complexity, many physicians are unaware of the disease and its complications. A major focus moving ahead will be to turn knowledge gaps and unmet needs into new research directions.

METHODS

On October 1-3, 2017, the Sturge-Weber Foundation assembled clinicians from the Clinical Care Network with patients from the Patient Engagement Network of the Sturge-Weber Foundation to identify our current state of knowledge, knowledge gaps, and unmet needs.

RESULTS

One clear unmet need is a need for consensus guidelines on care and surveillance. It was strongly recommended that patients be followed by multidisciplinary clinical teams with life-long follow-up for children and adults to monitor disease progression in the skin, eye, and brain. Standardized neuroimaging modalities at specified time points are needed together with a stronger clinicopathologic understanding. Uniform tissue banking and clinical data acquisition strategies are needed with cross-center, longitudinal studies that will set the stage for new clinical trials. A better understanding of the pathogenic roles of cerebral calcifications and stroke-like symptoms is a clear unmet need with potentially devastating consequences.

CONCLUSIONS

Biomarkers capable of predicting disease progression will be needed to advance new therapeutic strategies. Importantly, how to deal with the emotional and psychological effects of Sturge-Weber syndrome and its impact on quality of life is a clear unmet need.

Clinical outcomes of Ahmed glaucoma valve implantation in pediatric glaucoma

PURPOSE:

To evaluate the outcomes of Ahmed glaucoma valve implantation in refractory primary congenital glaucoma as well as primary procedure in aphakic glaucoma.

METHOD:

In this retrospective study, medical records of patients who underwent Ahmed glaucoma valve implantation for refractory glaucoma and aphakic glaucoma were reviewed. Primary outcome measures were the surgical success defined as intraocular pressure ≤21 mm Hg and decreased ≥20% and no secondary glaucoma surgery. Secondary outcome measures were the number of glaucoma medications, complications, best corrected visual acuity, and intraocular pressure.

RESULTS:

A total of 62 eyes of refractory primary congenital glaucoma patients (group 1) and 33 eyes of aphakic glaucoma patients (group 2) were included in our study. Mean follow-up was 51 ± 33 months in group 1 and 49 ± 41 months in group 2 (p = 0.82). The cumulative probability of success was 90% in both groups at the first year; however, the success rate was 52.5% in group 1 and 71.5% in group 2 at 5 years' follow-up visit. In group 1, the mean intraocular pressure ± standard deviation was 33.1 ± 8.6 mm Hg at the baseline and decreased to 17.1 ± 5.3 mm Hg at 1 year and 18.5 ± 6.4 at 3 years postoperatively (all p's < 0.001). Corresponding values for group 2 were 28.9 ± 6.1, 15.2 ± 4.6, and 16.0 ± 5.9 mm Hg, respectively (all p's < 0.001). The baseline number of glaucoma medications was 3 ± 0.7 that decreased to 2 ± 0.8 at final follow-up (p = 0.02).

CONCLUSION:

Ahmed glaucoma valve implantation has a moderate success rate in the management of refractory primary congenital glaucoma with an increased chance of tube-related complications. The surgical success rate is higher in case of primary Ahmed glaucoma valve implant for aphakic glaucoma with acceptable safety profile.

Early Trabeculotomy Ab Externo in Treatment of Sturge-Weber Syndrome

PURPOSE

To evaluate the intermediate-term efficacy and safety of trabeculotomy in infant Sturge-Weber syndrome (SWS).

DESIGN

Retrospective cohort study.

METHODS

All SWS-induced glaucoma patients less than 12 months of age who underwent trabeculotomy at our Ophthalmology Department from August 2011 to March 2017 were reviewed. Baseline demographics, intraocular pressure (IOP), cup-to-disc ratio (C/D), and cornea diameters were noted before surgery. The IOP, success probabilities, and medication usage were recorded during follow-up until the last visit.

RESULTS

Overall, 34 eyes (32 patients) were included, with a median surgery age of 3 months and a median follow-up time of 15.5 months. The mean preoperative IOP, asymmetry between 2 eyes, cornea diameter, and median C/D were 21.5 ± 6.6 mm Hg, 10.1 ± 4.9 mm Hg, 12.6 ± 0.7 mm, and 0.65 (interquartile range [IQR]: 0.55, 0.80), respectively. The IOP was significantly reduced from the preoperative baseline at 1 week, 3 months, 6 months, 1 year, and 2 years after the surgery (P < .05). At the last follow-up, the cumulative proportions of overall and complete success were 86.6% and 66.0%, respectively. Complications included a transient shallow anterior chamber. Thirty of the 34 eyes had intraoperative hyphema, 27 of which lasted less than 3 days. No other complications were noted during the follow-up.

CONCLUSIONS

Compared to previous studies with a later diagnosis of glaucoma in SWS patients, better outcomes were achieved with an early diagnosis of glaucoma in SWS patients. Early trabeculotomy ab externo was safe and led to good intermediate-term surgical outcomes for early-onset glaucoma in SWS patients. Higher preoperative IOP and corneal edema were associated with a greater risk of surgery failure.