Primary congenital glaucoma outcomes: lessons from 23 years of follow-up

Childhood glaucoma: Implications for genetic counselling

Childhood glaucoma is a heterogeneous group of ocular disorders defined by an age of onset from birth to 18 years. These vision-threatening disorders require early diagnosis, timely treatment, and lifelong management to maintain vision and minimise irreversible blindness. The genetics of childhood glaucoma is complex with both phenotypic and genetic heterogeneity. The purpose of this review is to summarise the different types of childhood glaucoma and their genetic architecture to aid in the genetic counselling process with patients and their families. We provide an overview of associated syndromes and discuss implications for genetic counselling, including genetic testing strategies, cascade genetic testing, and reproductive options.

Progression to bilaterality in unilateral primary congenital glaucoma

PURPOSE

To evaluate the incidence of rise in intraocular pressure (IOP) in fellow eyes of patients with unilateral primary congenital glaucoma (PCG) and to identify risk factors for IOP increase over long-term follow-up.

METHODS

The medical records of unilateral PCG patients who had completed at least 5 years of follow-up were reviewed retrospectively. The incidence of developing ocular hypertension / glaucoma in fellow eyes was analyzed. Fellow eye progressors were those which showed an increase in optic nerve cupping by at least 0.2 since the first presentation or had IOP of >21 mm Hg on two occasions. The risk factors for progression that were analyzed included IOP, visual acuity, axial length, central corneal thickness (CCT), corneal diameters (CD), presence or absence of angle dysgenesis on high-resolution anterior segment optical coherence tomography (AS-OCT), and morphology of aqueous outflow pathways.

RESULTS

After a median follow-up of 8.2 years (range, 5-25.5) progression to bilateral disease was found in 17 of 54 patients (32%), of whom 8 (15%) developed ocular hypertension and 9 (17%) developed glaucoma in the fellow eye. Among the unaffected fellow eyes, those with a larger CD (>12 mm), measured after at least 5 years' follow-up, were ten times more likely to progress (P = 0.01; OR = 9.5 [95% CI, 1.7-54.3]). The presence of a patent supraciliary channel was significantly more frequently associated in fellow eyes compared with affected eyes on AS-OCT (OR = 1.4 [95% CI, 0.46-4.68]).

CONCLUSIONS

One-third of unaffected fellow eyes of unilateral PCG eventually progress over time, most often after 5 years. Larger CD at follow-up in the fellow eye is strongly predictive for progression.

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.

Chromatic vision and structural assessment in primary congenital glaucoma

Primary congenital glaucoma is a rare disease that occurs in early birth and can lead to low vision. Evaluating affected children is challenging and there is a lack of studies regarding color vision in pediatric glaucoma patients. This cross-sectional study included 21 eyes of 13 children with primary congenital glaucoma who were assessed using the Farnsworth D-15 test to evaluate color vision discrimination and by spectral domain optical coherence tomography to measure retinal fiber layer thickness. Age, visual acuity, cup-to-disc ratio and spherical equivalent data were also collected. Global and sectional circumpapillary and macular retinal fiber layer thicknesses were measured and compared based on color vision test performance. Four eyes (19%) failed the color vision test with diffuse dyschromatopsia patterns. Only age showed statistical significance in color vision test performance. Global and sectional circumpapillary and macular retinal fiber layer thicknesses were similar between the color test outcomes dyschromatopsia and normal. While the color vision test could play a role in assessing children with primary congenital glaucoma, further studies are needed to correlate it with damage to retinal fiber layer thickness.

Long-term functional and structural outcomes in patients with primary congenital glaucoma-A Danish nationwide study

PURPOSE

Evaluation of long-term functional and structural outcomes in patients with primary congenital glaucoma (PCG) based on visual acuity (VA), visual field (VF) using standard automated perimetry, and peripapillary retinal nerve fibre layer thickness (pRNFL).

METHODS

We retrospectively reviewed medical records of all patients diagnosed with PCG in Denmark from 1977 to 2016. Severe vision loss was defined as VA <6/60 and/or VF >20 decibels (dB). Prognostic factors were evaluated in a correlation matrix.

RESULTS

The median age of the 94 patients (153 PCG eyes) was 12 years (IQR 9-16). In PCG eyes 62% had VA ≥6/18 but 22% had <6/60. VA in the better seeing eye was ≥6/18 in 90% and <6/60 in 5%. VF was measured in 59 PCG eyes and the median mean defect was 5.1 dB (IQR 2.1-9.6) with 52% better than 6 dB and 9% worse than 20 dB. Generalized pRNFL was reduced below the age-expected 1st percentile in 29% of the 58 PCG eyes where pRNFL was measured. Poor VA, poor VF and reduced pRNFL were all correlated (p = 0.0001). More surgeries (p < 0.0001) and longer diagnostic delay (p = 0.004) were associated with poorer vision and to a lesser degree with poor VF pRNFL.

CONCLUSION

In Denmark, most patients with bilateral PCG retain VA ≥6/18 in the better seeing eye. Poor VA was associated with poor VF. Longer diagnostic delay and more surgeries were associated with a poorer prognosis.

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.

Epidemiology and long-term outcomes of primary congenital glaucoma: a population-based study

BACKGROUND/OBJECTIVES

to establish the incidence, prevalence and long-term outcomes of primary congenital glaucoma (PCG) in Northern Ireland's general and Irish Traveller (IT) populations over a 59-year period.

SUBJECTS/METHODS

chart review of all PCG cases in Northern Ireland between 1962 and 2020. Incidence and prevalence were calculated with the aid of national population statistics. Long-term outcomes were analysed for eyes with at least 5 years follow up. Visual outcomes were stratified into groups: good-VA ≥ 6/12; moderate-VA 6/12 to 6/60, poor-VA < 6/60. Kaplan-Meier analysis was constructed to determine the probability of eyes retaining a good visual outcome over time. Outcomes of different surgeries were compared with regard to final vision, re-operations and complications.

RESULTS

57 PCG cases were identified between 1962 and 2020. Overall incidence was 3.4 per 100,000 live births. PCG prevalence in general and IT populations in 2019 was 4.3 per 100,000 and 238 per 100,000, respectively. Sixty eyes had sufficient data for long-term outcome analysis with a mean of 20.5 years follow up, 58% of which had good final visual outcome. Fifty-seven percent of eyes required multiple surgeries. Visual outcomes between trabeculectomies and tubes were comparable; however, there were more serious complications and reoperations associated with tubes.

CONCLUSIONS

Incidence of PCG in NI is similar to Great-Britain and Ireland; however, PCG appears to be particularly prevalent within IT community. Although a good visual outcome can be achieved in the majority of patients, a subset of cases remain challenging to manage despite surgical advances.

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.

Evaluation of visual field changes with retinal nerve fiber layer thickness in primary congenital glaucoma

Purpose

To evaluate visual field changes in primary congenital glaucoma (PCG) with retinal nerve fiber layer thickness on optical coherence tomography.

Methods

In this cross-sectional, observational study, consecutive PCG children who underwent combined trabeculotomy with trabeculectomy and on regular follow-up were enrolled. All patients were aged over four years and co-operative for RNFL OCT and visual field examination. Perimetry was done on Humphrey visual field (HVF) analyzer using 30-2 and 10-2 SITA standard algorithms as appropriate. If a reliable automated perimetry was not feasible, kinetic perimetry was done. The following were noted at baseline and every follow-up: age, sex, visual acuity, intraocular pressure (IOP), cup-disc ratio (CDR), corneal diameters, refraction, any topical antiglaucoma medications, surgeries underwent, age at surgery and duration between surgery and final examination.

Results

Forty-eight eyes of 34 children operated for PCG and 19 eyes of 17 controls were analyzed. A statistically significant thinner average RNFL thickness of 87.2 ± 28 μm was noted in PCG eyes as compared to controls with 100.6 ± 7.2 μm (P = 0.04). The mean cup-disc area ratio on OCT in PCG eyes was 0.43 ± 0.2 (0.02-0.93) and in control eyes was 0.23 ± 0.07 (0.1-0.4) (P < 0.001). On RNFL OCT, there was significant focal RNFL loss in temporal superior (P = 0.003), nasal inferior (P = 0.037) and temporal inferior (P < 0.001) quadrants compared to controls. Among PCG eyes, 20/48 eyes (41.7%), had definitive, reproducible glaucomatous VF defects. Mean baseline IOP in PCG eyes with VF defect was 28.7 ± 5.7 mmHg and in eyes with normal VF was 24.6 ± 5.9 mmHg (P = 0.03). On univariate regression analysis, higher baseline IOP was significantly associated with both RNFL loss (odds ratio (OR): -2.17) and VF defects (OR: 3.35). Fluctuation in follow-up IOP (OR: 3.33) was also significantly associated with the presence of VF defects. On multivariable regression analysis maximum, IOP was significantly associated with RNFL loss and VF defects.

Conclusion

Peripapillary RNFL thickness could be used to identify PCG eyes having visual field loss and possibly poor visual function from PCG eyes without visual field defects. Baseline and follow-up IOP, significantly correlated with RNFL thickness in PCG eyes.

Quality of life in children with glaucoma: a qualitative interview study in Australia

OBJECTIVE

Childhood glaucoma is a chronic vision-threatening condition that may significantly impact an individual's psychosocial well-being. There is a paucity of literature investigating the quality of life (QoL) in children with glaucoma. The aim of this study was to investigate and report on the QoL issues encountered by children with glaucoma.

DESIGN

This is a qualitative interview study. Data were collected through semistructured interviews. NVivo V.12 software (QSR International Pty Ltd, Melbourne, Australia) was used to analyse and code data to identify QoL themes. The prominence of QoL themes was determined by the number of children who raised issues connected to the corresponding theme.

SETTING

Interviews were conducted via telephone or videoconferencing between April 2020 and July 2021.

PARTICIPANTS

Eighteen children with glaucoma, aged 8-17 years, who resided in Australia, were recruited from the Australian and New Zealand Registry of Advanced Glaucoma.

RESULTS

Median child age was 12.1 years (IQR: 9.7-14.5 years) and 33% were female. Seven QoL themes were identified: 'coping', 'inconveniences' and 'emotional well-being' were more prominent themes than 'symptoms', 'ocular health concerns', 'social well-being' and 'autonomy'. Adaptive coping strategies included resilience throughout clinical examinations and establishing positive relationships with ophthalmologists. These minimised inconveniences related to clinic waiting times and pupillary dilatation. External to the clinical setting, children often dissociated from their glaucoma but struggled with glare symptoms and feeling misunderstood by fellow peers. Older children aged 13-17 years commonly disengaged from their glaucoma care and expressed an unwillingness to attend ophthalmic appointments. Older children further raised issues with career options, obtaining a driver's licence and family planning under the theme of autonomy.

CONCLUSIONS

The psychosocial impact of childhood glaucoma extends beyond the clinical environment and was minimised using coping strategies. Older children may require additional social and ophthalmic support as they transition into adulthood.

Preparation of a Single Cell Suspension from the Murine Iridocorneal Angle

Single cell RNA sequencing is a powerful tool that can be used to identify distinct cell types and transcriptomic differences within complex tissues. It has proven to be especially useful in tissues of the eye, where investigators have identified novel cell types within the retina, anterior chamber, and iridocorneal angle and explored transcriptomic contribution to disease phenotypes in age-related macular degeneration. However, to obtain high quality results, the technique requires isolation of healthy single cells from the tissue of interest, seeking complete tissue digestion while minimizing stress and transcriptomic changes in the isolated cells prior to library preparation. Here, we present a protocol developed in our laboratory for isolation of live single cells from the murine iridocorneal angle, which includes Schlemm's canal and the trabecular meshwork, suitable for single cell RNA sequencing, flow cytometry, or other downstream analysis. Graphical abstract.

Success Rate of Augmented Trabeculectomy in Primary Congenital Glaucoma

PURPOSE

To evaluate the outcome of trabeculectomy augmented with mitomycin C in primary congenital glaucoma and to document the complications of the procedure in young children.

METHODS

This was a prospective study of children younger than 2 years with primary congenital glaucoma who were treated with primary trabeculectomy with mitomycin C. After surgery, patients were observed for a minimum of 1 year. Trabeculectomy success was defined as an intraocular pressure (IOP) of 21 mm Hg or less without (absolute success) or with (qualified success) topical antiglaucoma medications. Surgical success was assessed at 1, 6, and 12 months after the procedure.

RESULTS

Seventy-four eyes of 42 children were included in the current study. The mean age was 11.7 ± 8.5 months. Of the 42 children, 57.2% were male and 42.8% were female. The mean IOP after surgery was significantly lower than the preoperative IOP (P < .0001). Absolute success was observed in 98.6%, 50%, and 27% of eyes at 1, 6, and 12 months, respectively. Qualified success was achieved in 1.4%, 36.5%, and 48.6% of eyes at 1, 6, and 12 months, respectively. Overall success of the procedure was 100% at 1 month but reduced to 86.5% at 6 months and 75.7% at 12 months. In 24.3% of eyes, IOP was not controlled even with adjunctive topical glaucoma medications and was considered a failure. Postoperative complications were shallow anterior chamber (10.8%), collapsed anterior chamber (1.3%), and choroidal detachment (12.0%). Complications were managed conservatively, and 6 eyes needed surgical intervention.

CONCLUSIONS

Augmented trabeculectomy is a useful primary procedure in children with primary congenital glaucoma. Topical glaucoma medications supplement the success of the procedure. [J Pediatr Ophthalmol Strabismus. 2022;59(3):180-186.].

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.

Combined trabeculotomy-trabeculectomy for primary congenital glaucoma: long-term experience from a tertiary referral centre in a developing nation

PURPOSE

To evaluate the long-term visual and surgical outcomes, and associated risk factors for poor outcomes in patients with primary congenital glaucoma (PCG).

METHODS

Retrospective review of medical records of children who underwent combined trabeculotomy-trabeculectomy (CTT) without mitomycin-C as the first surgical procedure by a single surgeon between January 1990 and December 2010. Success was defined as intraocular pressure (IOP) <16 mmHg without (complete) or with (qualified) one glaucoma medication. We used the WHO criteria of vision loss to categorize the levels of vision impairment (VI). For purposes of statistical analysis, we randomly chose one eye of patients for bilateral PCG and affected eye in unilateral PCG.

RESULTS

The cohort included 653 consecutive PCG patients (1128 eyes; mean age, 26 months), of whom 475 (73%) underwent simultaneous bilateral CTT. Kaplan-Meier survival analysis revealed 1-, 5-, 10-, 15-, and 19-year complete success rates of 92.6% (n = 372), 75.5% (n = 173), 55.9% (n = 72), 44.7% (n = 19), and 21.6% (n = 3), respectively. Multivariate analysis revealed independent associations between failure, preoperative corneal clarity, and prior glaucoma surgery. Mean follow-up was 41 ± 51 months (range, 6 months to 19 years; median, 1 year). Of the visual acuity (VA) data in the affected eyes obtained at last follow-up (n = 333, 51%), seventy-four patients (22%) had VA of ≥6/12. Of the remaining 259 patients, 18 (7%) had mild VI, 87 (34%) had moderate VI, 58 (22%) had severe VI, and 96 (37%) were blind. No serious complications were noted.

CONCLUSIONS

Primary CTT may be safely employed to control IOP and may provide long-term benefits in PCG patients.

Approach to childhood glaucoma: A review

Childhood glaucoma represents a heterogenous group of rare ocular conditions that may result in significant sight threatening complications related to elevated intraocular pressure (IOP). It can be classified as either primary or secondary and the latter may have systemic associations. This review will be based on the work of the childhood glaucoma research network (CGRN) and will focus on the diagnosis and management of the most common types of childhood glaucoma. These include primary congenital glaucoma (PCG) and juvenile open angle glaucoma (JOAG) as well as secondary causes of glaucoma associated with non-acquired ocular anomalies (Axenfeld-Rieger anomaly; Peters anomaly and Aniridia), glaucoma associated with systemic disease (Sturge Weber syndrome and Neurofibromatosis), those due to acquired conditions (Uveitic glaucoma, trauma and tumours) and importantly glaucoma following cataract surgery.

The caregiver experience in childhood glaucoma: An interview study

PURPOSE

To investigate and report on the quality of life (QoL) issues experienced by caregivers of individuals with childhood glaucoma.

DESIGN

Exploratory qualitative study PARTICIPANTS: Thirty-five caregivers of individuals with childhood glaucoma (defined as disease onset <18 years) recruited from the Australian and New Zealand Registry of Advanced Glaucoma.

METHODS

A qualitative research methodology (interpretive phenomenology) was applied. Data were collected through semi-structured in-depth interviews. NVivo-12 software (QSR International Pty Ltd) was used to inductively analyze, code, and organize data into QoL themes.

MAIN OUTCOME MEASURES

Quality of life themes and their sub-themes.

RESULTS

The mean caregiver age was 50.2 ± 13.6 years and 27/35 (77%) were mothers of an individual with childhood glaucoma. A total of six QoL themes were identified. Coping strategies and emotional well-being were the most prominent themes. Caregivers frequently adopted problem-focused adaptive coping strategies including partner and/or peer support and normalization. A caregivers' psychosocial well-being was often impacted by feelings of guilt and regret regarding their child's delayed diagnosis, fear and anxiety related to medical and social support, and loss of control as their child developed medical autonomy. The effect of family planning from the perspective of the caregiver formed a novel QoL theme and was associated with normalization and parental confidence in management of the condition.

CONCLUSION

Childhood glaucoma poses a substantial threat to a caregivers' psychosocial well-being. Strategies which promote normalization, peer support, psychotherapeutic intervention and genetic counseling may be indicated and indeed critical to the caregiver as they adapt to supporting their child with glaucoma.

Characteristics and long-term outcomes of childhood glaucoma: a retrospective-cohort study

Purpose: To evaluate the clinical characteristics and treatment outcomes of patients with childhood glaucoma.

Methods: We retrospectively reviewed the data of patients with childhood glaucoma who visited the glaucoma clinics at the Queen Sirikit National Institute of Child Health and the King Chulalongkorn Memorial Hospital between January 2008 and January 2018. The diagnosis was based on the Childhood Glaucoma Research Network classification. We recorded their clinical characteristics and requirement of any glaucoma interventions.

Results: A total of 691 eyes from 423 patients were included in this study. The patients predominantly comprised boys. The average follow-up duration was 71.3±63.8 months. The mean age at presentation was 3.9±4.4 years. Most patients presented with a high initial intraocular pressure (IOP). The average intial IOP of all patients was 28.5±11.2 mmHg. Glaucoma associated with non-acquired ocular anomalies (22.9%) was the most common subtype, followed by primary congenital glaucoma (20.8%). We recorded a family history of glaucoma in 6.4% of patients of the 234 patients with an available family history. Most patients had bilateral glaucoma (63.4%) and required at least one intervention (51.5%). The average IOP at the latest follow-up visit was 19.1±10.8 mmHg. All glaucoma types had significantly lower IOP, compared to that at their baselines (all p<0.001). Moreover, most patients had an unfavourable visual acuity (49.5%) at their latest visit.

Conclusions: Secondary glaucoma associated with non-acquired ocular anomalies is the most common subtype of glaucoma. The majority of patients had unfavourable visual outcomes. These real-world findings are fundamental to acquire a better understanding of childhood glaucoma.

Cellular crosstalk regulates the aqueous humor outflow pathway and provides new targets for glaucoma therapies

Primary congenital glaucoma (PCG) is a severe disease characterized by developmental defects in the trabecular meshwork (TM) and Schlemm's canal (SC), comprising the conventional aqueous humor outflow pathway of the eye. Recently, heterozygous loss of function variants in TEK and ANGPT1 or compound variants in TEK/SVEP1 were identified in children with PCG. Moreover, common variants in ANGPT1and SVEP1 have been identified as risk alleles for primary open angle glaucoma (POAG) in GWAS studies. Here, we show tissue-specific deletion of Angpt1 or Svep1 from the TM causes PCG in mice with severe defects in the adjacent SC. Single-cell transcriptomic analysis of normal and glaucomatous Angpt1 deficient eyes allowed us to identify distinct TM and SC cell populations and discover additional TM-SC signaling pathways. Furthermore, confirming the importance of angiopoietin signaling in SC, delivery of a recombinant ANGPT1-mimetic promotes developmental SC expansion in healthy and Angpt1 deficient eyes, blunts intraocular pressure (IOP) elevation and RGC loss in a mouse model of PCG and lowers IOP in healthy adult mice. Our data highlight the central role of ANGPT1-TEK signaling and TM-SC crosstalk in IOP homeostasis and provide new candidates for SC-targeted glaucoma therapy.

Quality of Life in Adults with Childhood Glaucoma: An Interview Study

PURPOSE

To explore and report on the quality-of-life (QoL) issues encountered by adults with childhood glaucoma.

DESIGN

Exploratory qualitative study.

PARTICIPANTS

Forty-seven participants with childhood glaucoma (defined as disease onset <18 years) recruited from the Australian and New Zealand Registry of Advanced Glaucoma (ANZRAG).

METHODS

A qualitative research methodology (interpretive phenomenology) was applied, and data were collected through semistructured in-depth interviews. NVivo-12 software (QSR International Pty Ltd) was used to inductively analyze and code data to identify QoL themes pertinent to the cohort studied.

MAIN OUTCOME MEASURES

Quality-of-life themes and subthemes.

RESULTS

Mean participant age was 40.0 ± 15.3 years, and 55% of participants were female. We identified 10 QoL themes pertinent to adults living with childhood glaucoma. Coping strategies and emotional well-being were the most prominent themes. Maladaptive coping strategies, including treatment nonadherence, were observed more commonly in individuals aged <40 years and those without a vision impairment or reviewed less regularly. Emotional well-being was affected by feelings of being misunderstood because of the rarity of the condition, being self-conscious of physical manifestations of the disease, and anxiety related to possible disease progression and vision loss. The effect of childhood glaucoma on family planning formed a novel QoL theme and included worry for their child to inherit the condition and an inability to fulfill parental duties. This often led to genetic counseling-seeking behaviors. Mobility issues were infrequently experienced.

CONCLUSIONS

Childhood glaucoma poses a substantial impact to the emotional well-being of adults with the condition, which is mediated by the use of coping strategies. Genetic counseling and family planning options may be important. This study supports the development of a childhood glaucoma-specific patient-reported outcome measure for assessment of the psychosocial impact of childhood glaucoma in adults.

Primary congenital glaucoma surgery: outcomes and visual function

Purpose

To assess the long-term visual outcomes of children with PCG, irrespective of the type of surgical procedure, and to create visual acuity curves to help in predicting the development of visual function in these patients. The secondary aim is to identify associated factors for visual decline or loss, highlighting differences between neonatal and infantile subgroups.

Methods

The medical records of pediatric glaucoma patients from 1996 to 2017 at the University Hospital of Verona (Verona, Italy) were retrospectively reviewed. Visual acuities, surgeries, PCG subtype and etiology of vision impairment were recorded. Statistical analyses were performed to detect factors associated with vision decline.

Results

Sixty-seven eyes (40 patients) were included in the study. Developmental predictive curves of visual acuity showed that children with infantile PCG had a better visual outcome than children with neonatal PCG at each step of follow-up. A good-to-moderate VA (< 1 LogMAR) was achieved in 56 eyes (83.6%), while 11 eyes (16.4%) had poor VA (≥ 1 LogMAR). The age at onset, sex, number of surgeries, intraocular pressure (IOP) control (with or without antiglaucoma drugs), axial length (AL) and corneal opacities were statistically associated with vision impairment (p < 0.01). The main cause of visual impairment was amblyopia.

Conclusions

Visual outcomes of PCG significantly correlate with the age at diagnosis. Although a good long-term IOP control can often be achieved in PCG, often the visual acuity remains below the lower limits of the normal range. Poor vision in childhood is related to global developmental problems, and referral to third-level services should not be delayed to prevent vision impairment. In this regard, visual acuity curves can be a useful tool for the consultant ophthalmologist to define the visual development of children affected by PCG.

Incidence, Comorbidity, and Mortality of Primary Congenital Glaucoma in Korea from 2001 to 2015: A Nationwide Population-based Study

Purpose

To report incidence rates of primary congenital glaucoma in Korea and evaluate comorbidity and mortality from 2001 to 2015.

Methods

This study is a nationwide and retrospective population-based study. We used claims data from the Korean National Health Insurance Service database between 2001 and 2015. Data for all patients diagnosed with primary congenital glaucoma were retrieved using the Korean Electronic Data Interchange and Korean Standard Classification of Diseases-6 codes.

Results

The number of patients with primary congenital glaucoma between 2001 and 2015 was 776, of which 437 were male (56.31%) and 339 were female (43.69%). The annual prevalence demonstrated a general decreasing trend since 2011, but this was not significant. Over the total survey period, the incidence rate was 11.0 per 100,000 births, with 12.0 cases among males and 10.0 among females. The incidence according to age was 518 (68.78%) patients at age 0, 112 (13.66%) at 1 year, 70 (8.39%) at 2 years, and 76 (9.17%) at 3 years. Of the 776 patients diagnosed with primary congenital glaucoma in the study population, 27 died. The observed mortality per 100,000 people is about 10 times higher than that of the general infant and child population under the age of 4 years. Visual impairment was the most common accompanying disability, followed by brain lesion.

Conclusions

Our study's estimates of the nationwide population-based incidence of primary congenital glaucoma in a Korean population will expand our understanding of the disease and allow healthcare systems to plan for primary congenital glaucoma.

Long-term structural and functional outcomes of primary congenital glaucoma

PURPOSE

To investigate the clinical characteristics and long-term outcomes of primary congenital glaucoma (PCG) patients.

METHODS

In this retrospective, longitudinal, cohort study, PCG patients with reliable visual field (VF) tests and optical coherence tomography (OCT) were included. Disease progression was detected using guided progression analysis with OCT and the change analysis of mean deviation (MD) slope with VF tests. Factors associated with the disease progression and visual prognosis were analyzed.

RESULTS

Twenty-nine eyes from 11 bilateral and 7 unilateral PCG patients were enrolled. LogMAR visual acuity declined (0.15 vs. 0.40, P < 0.001). The change rate of the average retinal nerve fiber layer thickness was - 0.83 ± 1.45 µm/year, and 28% of eyes showed glaucoma progression on OCT. The median of the MD slope was 0.16 (- 1.19 to 1.07) dB/year, and 14% of eyes showed glaucoma progression on the VF test. Higher average intraocular pressure (IOP) (P = 0.046) and IOP fluctuation (P = 0.031) predicted disease progression. None of the fellow eyes of unilateral PCG patients developed glaucoma during the follow-up. At last, 59% of eyes had visual acuity > 20/70, and 31% had MD >  - 6 dB. Patients with worse baseline visual acuity (P = 0.027), worse baseline MD (P < 0.001), and smaller neuroretinal rim area (P < 0.001) showed worse final MD values.

CONCLUSIONS

Aggressive IOP control is necessary to prevent structural and functional decline in PCG patients. Their fellow eyes are not at risk of glaucoma. Baseline neuroretinal rim area can predict the functional outcome.

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.

Characteristics and long-term outcomes of childhood glaucoma: a retrospective-cohort study

Purpose: To evaluate the clinical characteristics and treatment outcomes of patients with childhood glaucoma. Methods: We retrospectively reviewed the data of patients with childhood glaucoma who visited the glaucoma clinics at the Queen Sirikit National Institute of Child Health and the King Chulalongkorn Memorial Hospital between January 2008 and January 2018. The diagnosis was based on the Childhood Glaucoma Research Network classification. We recorded their clinical characteristics and requirement of any glaucoma interventions. Results: A total of 691 eyes from 423 patients were included in this study. The patients predominantly comprised boys. The average follow-up duration was 71.3±63.8 months. The mean age at presentation was 3.9±4.4 years. Most patients presented with a high initial intraocular pressure (IOP). The average intial IOP of all patients was 28.5±11.2 mmHg. Glaucoma associated with non-acquired ocular anomalies (22.9%) was the most common subtype, followed by primary congenital glaucoma (20.8%). We recorded a family history of glaucoma in 6.4% of patients of the 234 patients with an available family history. Most patients had bilateral glaucoma (63.4%) and required at least one intervention (51.5%). The average IOP at the latest follow-up visit was 19.1±10.8 mmHg. All glaucoma types had significantly lower IOP, compared to that at their baselines (all p<0.001). Moreover, most patients had an unfavourable visual acuity (49.5%) at their latest visit. Conclusions: Secondary glaucoma associated with non-acquired ocular anomalies is the most common subtype of glaucoma. The majority of patients had unfavourable visual outcomes. These real-world findings are fundamental to acquire a better understanding of childhood glaucoma.

Differences in outflow channels between two eyes of unilateral primary congenital glaucoma

PURPOSE

Primary congenital glaucoma (PCG) occurs in only one eye in some patients. We aimed to characterize anatomical features of the angle and Schlemm's canal (SC) in vivo among fellow eyes of patients with unilateral primary congenital glaucoma.

METHODS

Both eyes of 33 children with unilateral PCG and 30 healthy, age-matched children, old enough to co-operate were analysed using high-resolution anterior segment spectral domain (SD) OCT. Subgroup analysis was done for the presence/absence of angle dysgenesis as defined by the presence of abnormal tissue/hyper-reflective membrane within angle recess and/or the absence of SC. Other anatomical landmarks differentiating the fellow eyes from eyes with glaucoma were also evaluated and compared with healthy subjects.

RESULTS

The presence of abnormal tissue at the angle and/or a hyper-reflective membranous structure covering the meshwork was seen in all affected PCG eyes (100%) and in 21 (63%) unaffected fellow eyes; p = 0.001. The SC could be seen in 8 (24%) affected in comparison with 29 (88%) fellow unaffected eyes; p = 0.001. The ASOCT scans of 54 (90%) healthy eyes and 3 (9%) fellow PCG eyes revealed a direct communication of anterior portion of the SC with the anterior chamber. Among the fellow eyes, a communication of the supraciliary space with anterior chamber could be discerned in 26 eyes (79%).

CONCLUSIONS

Despite angle dysgenesis, outflow channels such as the uveoscleral or a direct communication of SC with the anterior chamber play a role in preventing the development of glaucoma in fellow eyes of unilateral PCG.

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.

Long-Term Surgical Outcomes of Primary Congenital Glaucoma in a South Indian Population

PURPOSE

To evaluate the long-term surgical outcomes of children with primary congenital glaucoma (PCG) in a South Indian population.

DESIGN

Retrospective cohort study.

PARTICIPANTS

Children with PCG who underwent primary surgery from 1997 through 2000 at a tertiary eye center in India with minimum of 5 years of follow-up.

METHODS

This retrospective cohort study included children with PCG who underwent trabeculotomy, trabeculectomy, or combined trabeculotomy and trabeculectomy (CTT) as primary surgery from 1997 through 2000 at a tertiary eye center in India with minimum of 5 years of follow-up. Survival analyses were performed to determine cumulative probability of complete and qualified success.

MAIN OUTCOME MEASURES

Intraocular pressure (IOP) control, glaucoma medication use, surgical success rates, and complications.

RESULTS

The study included 50 eyes of 31 patients. Mean age at initial surgery was 5 months (range, 5 days-48 months) and 19 patients (61.3%) showed bilateral disease. Mean duration of follow-up was 10.9 ± 3.10 years (range, 6-18 years). Mean IOP was reduced from 28.58 ± 9.78 mmHg (range, 10-59 mmHg) before surgery to 17.13 ± 7.62 mmHg after surgery (range, 5-42 mmHg; P < 0.001) at final follow-up. Survival analysis showed that the probability of surgical success with CTT was 77.8% at 1 year, 66.2% at 2 years, 53.0% at 5 years, and 16.6% at 15 years. Visual acuity at last available follow-up correlated with surgical success (P = 0.042).

CONCLUSIONS

Surgical success after long-term follow-up of children with PCG is low. The probability of surgical success declines over time. Children with PCG require life-long follow-up and management, even after initial surgical success, to prevent visual impairment and blindness.

Clinical profile and outcome of early surgery in neonatal-onset glaucoma presenting over a 5-year period

BACKGROUND

Neonatal-onset glaucoma (NOG) is a severe form of childhood glaucoma and is not always due to primary congenital glaucoma (PCG). Due to advances in neonatal care, the incidence of NOG is rising, but it remains an under-reported entity. The objective of the paper was to study the clinical profiles, surgical and visual outcomes of NOG at least 1 year following early surgery.

METHODS

Prospective interventional cohort study at a tertiary care referral centre. Babies with NOG, who presented between January 2013 and December 2017, had a history suggestive of disease onset within 1 month of birth, and underwent surgery by 3 months of age, were prospectively enrolled. Those who completed a 1-year follow-up after surgery were analysed.

RESULTS

94 eyes of 53 babies were analysed. 35 (66%) had PCG. Neonatal congenital ectropion uveae, congenital rubella syndrome, Peter's anomaly and Sturge-Weber syndrome comprised the non-PCG group. The mean age at presentation and surgery was 24.8±21.9, and 36.7±29.9 days. Additional glaucoma surgery was required in 43 of the 94 eyes (45.7%). PCG had significantly better outcomes than other glaucomas at all time points. 28.3% of eyes had good vision (LogMar (0-0.5)), 34.7% had moderate visual impairment (LogMar 0.7-1.0) and 16% were blind (LogMar <1.62) .

CONCLUSION

Our study shows that NOG does not always have a dismal prognosis. A small but significant proportion could have other underlying conditions than PCG. Timely surgery and rigorous amblyopia therapy resulted in good outcomes in terms of intraocular pressure control and vision in this cohort.

Clinical Characteristics and Prognostic Factors of Visual Outcomes in Childhood Glaucoma

PURPOSE

To determine the prognostic factors for poor visual outcomes in childhood glaucoma.

METHODS

The medical records of patients with childhood glaucoma diagnosed at age 4 years or younger who were treated surgically from 2002 to 2019 at Songklanagarind Hospital, Hatyai, Thailand, were retrospectively reviewed. Glaucoma subtypes, clinical characteristics, final visual acuity, and etiology of visual impairment were recorded. The generalized estimating equation for logistic regression analysis was used to determine prognostic factors for final visual acuity of worse than 20/200.

RESULTS

Forty-five eyes of 31 patients were included (33.3% had primary glaucoma and 66.7% had secondary glaucoma). At the final visit (mean: 6.8 years), 20.5% had good visual acuity (20/50 or better), 15.9% had fair visual acuity (worse than 20/50 to 20/200), and 63.6% had poor visual acuity (worse than 20/200). The major cause of visual impairment (worse than 20/50) was deprivation amblyopia. Prognostic factors for poor final visual acuity (worse than 20/200) were secondary glaucoma, age at diagnosis of younger than 3 months, and interval to surgery of more than 3 months. Eyes with a final visual acuity of better than 20/200 had higher mean intraocular pressure preoperatively that tended to increase postoperatively and every visit afterward compared to the other group.

CONCLUSIONS

Two-thirds of eyes with childhood glaucoma ended up with poor final vision. Early surgery to control intraocular pressure, along with amblyopia treatment, should be considered to prevent poor visual outcome. The prognostic factors for poor visual outcome can contribute to parental advice and planning of patient care. [J Pediatr Ophthalmol Strabismus. 2020;57(5):283-291.].

Lens-induced myopization and intraocular pressure in young guinea pigs

Background

Intraocular pressure (IOP) is an important physiological measure of the eye and is associated with some ocular disorders. We aimed to assess the influence of topical beta blocker-induced IOP reduction on lens-induced axial elongation in young guinea pigs.

Methods

The experimental study included 20 pigmented guinea pigs (age: 2–3 weeks). Myopia was induced in the right eyes for 5 weeks with − 10 diopter lenses. The right eyes additionally received either one drop of carteolol 2% (study group, n = 10) or one drop of artificial tears daily (control group, n = 10), while the contralateral eyes of all animals remained untouched. The outcome parameter was axial elongation during the follow-up period. The mean of all IOP measurements taken during the study was referred to as mean IOP.

Results

Greater axial elongation was associated with a shorter axial length at baseline (P < 0.001; standardized regression coefficient beta: − 0.54) and lens-induced myopization (P < 0.001; beta: 0.55). In the multivariable model, axial elongation was not significantly correlated with the IOP at study end (P = 0.59), the mean IOP during the study period (P = 0.12), the mean of all IOP measurements (P = 0.17), the difference between the IOP at study end and baseline IOP (P = 0.38), the difference between the mean IOP during the study period and the baseline IOP (P = 0.11), or the application of carteolol eye drops versus artificial tears eye drops (P = 0.07). The univariate analysis of the relationships between axial elongation and the IOP parameters yielded similar results. The inter-eye difference between the right eye and the left eye in axial elongation was significantly associated with the inter-eye difference in baseline axial length (P = 0.001; beta:-0.67) but not significantly correlated with the inter-eye difference in any of the IOP-related parameters (all P > 0.25).

Conclusions

In young guinea pigs with or without lens-induced axial elongation, neither the physiological IOP nor the IOP reduced by carteolol, a topical beta-blocker, was associated with the magnitude of axial elongation. These results suggest that IOP, regardless of whether it is influenced by carteolol, does not play a major role in axial elongation in young guinea pigs.

Surgical Outcomes in Children With Primary Congenital Glaucoma: An Eight-Year Experience

Background

Primary congenital glaucoma (PCG) is a congenital anomaly arising from an unusual development of the filtration angle, causing a remarkable rise in intraocular pressure (IOP) that is irrelevant to other ocular or systemic deformities.

Purpose

The aim of the current study was to evaluate the surgical outcome in PCG patients between 2011 and February 2019.

Methods

This was a retrospective study of PCG patients who underwent trabeculotomy, trabeculectomy, deep sclerectomy, Ahmed valve, and/or cyclophotocoagulation (CPC) at a tertiary hospital. The IOP must be equal or less than 21 mmHg with or without medication to be designated a successful surgery.

Results

A total of 80 eyes (41 patients) were included in the study, with a slight male predominance of 65.9%. At presentation, the most reported age group was under 30 days (46.3%). Moreover, deep sclerotomy was the most common procedure, followed by CPC, which were performed in 48 (58.5%) and 18 (21.9%) eyes, respectively. In the overall group, the mean initial IOP was 23.65±8.52 mmHg, while the mean IOP was 16.73±8.56 mmHg at final follow-ups (p < 0.001), with a 46% reduction. The mean axial length showed a slight progression from 21.11±2.58 at the initial visit to 22.92±3.57 mm at the last follow-up (p<0.001). However, the mean horizontal diameter increased from 12.63±1.83 mm at the initial visit to 13.31±1.13 mm at the final visit (p=0.004).

Conclusion 

An excellent IOP reduction could be accomplished in the majority of eyes. Deep sclerectomy can effectively reduce IOP in PCG without the occurrences of serious complications that are commonly seen after other procedures like trabeculectomy or trabeculotomy.

Ab externo 240-degree trabeculotomy versus trabeculotomy-trabeculectomy in primary congenital glaucoma

OBJECTIVE

This prospective study aimed to compare the surgical outcomes of ab externo 240-degree trabeculotomy and trabeculotomy-trabeculectomy in managing primary congenital glaucoma (PCG).

PATIENTS AND METHODS

The study included 30 eyes of 30 patients aged less than 3 years who were diagnosed with PCG and was conducted in Menofia University Hospital between November 2018 and January 2020. The studied eyes were divided into two equal groups. Ab externo 240-degree trabeculotomy and combined trabeculotomy with trabeculectomy with MMC were performed for groups I and II, respectively. Post-operative measurements included intraocular pressure (IOP), optic disc changes, alteration in corneal clarity and transverse corneal diameter, as they are needed for antiglaucoma therapy. Post-operative complications were followed up for 1-year.

RESULTS

There was significant reduction in IOP in both groups during the follow-up period. The reduction was higher in group I, where mean preoperative IOP was 28.20 ± 1.74 mmHg. The IOP in the group II was 28.07 ± 3.51 mmHg. The mean IOP decreased to 13.93 ± 1.8 mmHg and 14.60 ± 1.24 mmHg in groups I and II, respectively, after 1 year (P < 0.001); however, the difference between the two groups was not significant. Regarding post-operative complications, post-operative hypotony was more common in group I. Other complications such as shallow anterior chamber, choroidal detachment and blebitis occurred more frequently in group II. However, post-operative hyphema was more common in group I. Corneal clarity improved significantly in both groups, but more so in group I, where an improvement was seen in 13 cases (86.6%), compared to 11 cases in group II (73.3%).

CONCLUSION

Ab externo 240° trabeculotomy and trabeculotomy-trabeculectomy are effective techniques in primary congenital glaucoma with more reduction in IOP in Ab Externo 240° trabeculotomy. Ab externo 240° trabeculotomy provided more better surgical outcome with limited complications, especially those related to bleb formation.

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.

Referral patterns of children with glaucoma and their caretakers in Northern Tanzania

AIM

To describe the referral patterns of children with primary childhood glaucoma (PCG) or secondary childhood glaucoma (SCG) and their presenting symptoms in Northern Tanzania.

METHODS

A retrospective observational study of children <17y with PCG or SCG who were referred to Kilimanjaro Christian Medical Centre (KCMC) Eye Department between 2000 and 2013 was conducted. Presenting symptoms, age at presentation, place of origin, distance to hospital, type of glaucoma, visual acuity, optic disc appearance (vertical cup-to-disc ratio) and type of referral were described.

RESULTS

Seventy patients with PCG and 27 patients with SCG were included in the study. Median age at first presentation was 1y in the PCG group (range 0-16y) and 9y in the SCG group (range 1-15y). In both groups around 87% of the children presented already with low vision (logMAR>0.48, better eye). Most of the children (60%) and their caretakers presented on their own initiative, while 24% were sent by different general health cadres and 16% by eye care professionals. Buphthalmos was the main symptom mentioned as a trigger for presentation.

CONCLUSION

The study shows that most of the children presented late resulting in advanced stages of glaucoma at the time of initiation of treatment. The majority attended the referral eye department on their own initiative with buphthalmos being the most commonly described symptom. Awareness creation among caretakers of children, general health and eye care providers, ideally embedded in general child health promotion activities, is needed to increase and accelerate referrals.

Primary congenital glaucoma in Denmark, 1977-2016

PURPOSE

To perform an epidemiological survey of all patients in Denmark diagnosed with primary congenital glaucoma (PCG) from 1977 to 2016.

METHODS

A retrospective, nationwide study based on a review of medical files of all children with PCG born in Denmark from 1977 to 2016. PCG was defined as glaucoma due to isolated angle dysgenesis affecting children from birth and including late onset/late recognized PCG, excluding glaucoma associated with other congenital abnormalities. Incidence and risk factors of PCG including gender, consanguinity, family history, ethnicity, comorbidity and prematurity were evaluated and stratified by decade (1977-1986, 1987-1996, 1997-2006 and 2007-2016). Age at first symptoms, age at diagnosis, age at time of first surgery and possible diagnostic delay were assessed.

RESULTS

Of 118 patients were identified, annual incidence of PCG was 4.8 per 100 000 live born. 62.3% of cases were bilateral. The relative risk (RR) of PCG was significantly higher in boys (62.7% of patients, RR 1.60 (95% CI 1.10-2.32)). 13.6% had comorbidity. Median age at time of first symptoms was 75 days, median age at time of diagnosis was 150 days and median diagnostic delay was 75 days with no significant difference throughout the decades. Unilateral cases presented symptoms and were diagnosed significantly later than bilateral cases.

CONCLUSION

We provide unique nation-based information on the incidence of PCG from a single country covering 40 years. Male gender was a risk factor. Diagnostic delay was unchanged throughout the 4 decades and a high percentage of comorbidity was revealed. Introducing a standardized paediatric screening of all PCG children should be considered.

Characteristics of Pediatric Glaucoma in a Latin American Reference Center

Aim

To describe the clinical and epidemiological characteristics of children with pediatric glaucoma (PG) treated in an ophthalmologic national reference center.

Materials and methods

A retrospective study of patients diagnosed with PG in a national ophthalmologic reference center was made, between 2005 and 2015. Clinical findings, type of treatment, and the follow-up were evaluated.

Results

A total of 89 patients (145 eyes) were included. The median age of diagnosis was 2.0 years. The most frequent type of glaucoma was primary PG with 67.4% of affected patients, primary congenital glaucoma (PCG) being more frequent (69 eyes) than juvenile open-angle glaucoma (JOAG 36 eyes). Secondary PG accounted for 32.6% of the cases (40 eyes). At least one surgical procedure was needed in 56.6% of all studied eyes, and 10.7% of eyes had more than two surgical procedures. Even more, eyes with PCG had surgery in 88.4% of cases. On the contrary, eyes with JOAG did not require surgery. In the last assessment, the distribution of cases according visual acuity did not show differences. However, it is important to note that patients with secondary PG maintained a good vision only in 17.9% of cases.

Conclusion

Pediatric glaucoma is a heterogeneous group of diseases, and due to its low incidence, descriptive reports of large cohorts are not available. This study has a well-detailed report of PG characteristics in a national reference center. The frequency of JOAG in the present study was significantly higher than that reported in other studies. Also, clinical characteristics of all glaucoma described have some differences from data published.

Clinical significance

There are few studies that describe characteristics of PG. This study is an important tool to analyze the characteristics of PG in an effort to better know the disease.

How to cite this article

Saavedra C, Rios HA, Belalcazar S, et al. Characteristics of Pediatric Glaucoma in a Latin American Reference Center. J Curr Glaucoma Pract 2020;14(1):10–15.

Update in Genetics and Surgical Management of Primary Congenital Glaucoma

Primary congenital glaucoma (PCG) continues to be an important cause of visual impairment in children despite advances in medical and surgical treatment options. The progressive and blinding nature of the disease, together with the long lifespan of the affected population, necessitates a thorough understanding of the pathophysiology of PCG and the development of long-lasting treatment options. The first part of this review discusses the genetic features and makeup of this disorder, including all currently identified genetic loci (GLC3A, GLC3B, GLC3C and GLC3D) and relevant protein targets important for trabecular and Schlemm canal dysgenesis. These target molecules primarily include CYP1B1, LTBP2, and TEK/Tie2 proteins. Their potential roles in PCG pathogenesis are discussed with the purpose of bringing the readers up to date on the molecular genetics aspect of this disorder. Special emphasis is placed on functional implications of reported genetic mutations in the setting of PCG. The second part of the review focuses on various modifications and refinements to the traditional surgical approaches performed to treat PCG, including advances in goniotomy and trabeculotomy ab externo techniques, glaucoma drainage implant surgery and cyclodiode photocoagulation techniques that ultimately provide safer surgical approaches and more effective intraocular pressure control in the 21st century.

Childhood glaucoma genes and phenotypes: Focus on FOXC1 mutations causing anterior segment dysgenesis and hearing loss

Childhood glaucoma is an important cause of blindness world-wide. Eleven genes are currently known to cause inherited forms of glaucoma with onset before age 20. While all the early-onset glaucoma genes cause severe disease, considerable phenotypic variability is observed among mutations carriers. In particular, FOXC1 genetic variants are associated with a broad range of phenotypes including multiple forms of glaucoma and also systemic abnormalities, especially hearing loss. FOXC1 is a member of the forkhead family of transcription factors and is involved in neural crest development necessary for formation of anterior eye structures and also pharyngeal arches that form the middle ear bones. In this study we review the clinical phenotypes reported for known FOXC1 mutations and show that mutations in patients with reported ocular anterior segment abnormalities and hearing loss primarily disrupt the critically important forkhead domain. These results suggest that optimal care for patients affected with anterior segment dysgenesis should include screening for FOXC1 mutations and also testing for hearing loss.

Early Predictors of Long-term Outcomes in Childhood Glaucoma

PURPOSE

A data-based staging system for childhood glaucoma is likely to improve the prediction of visual acuity and intraocular pressure (IOP) control outcomes. We investigated early clinical factors associated with poor long-term visual, and IOP control outcomes in early-onset glaucoma as the initial steps to constructing a severity staging system.

DESIGN

Statistical modeling of retrospective case series data.

PARTICIPANTS

Glaucoma patients younger than 3 years of age who presented to Bascom Palmer Eye Institute between 1990 and 2010 with at least 5 years of follow up.

METHODS

Statistical modeling of retrospective case series data from first, second, third, 3-year, 5-year, and final visits.

MAIN OUTCOME MEASURES

Association of early clinical characteristics to final IOP-control outcomes and visual acuities.

RESULTS

A total of 26 eyes of 15 children were included. Nine of 15 (60%) of patients were male. Mean age at initial presentation: 9.98±10.55 months. Mean duration between initial and final visits: 11.13±3.55 years. By the third visit (mean 6.69 mo after presentation), presence of nystagmus, anterior segment dysgenesis (ASD) or having failed angle surgery increased the final LogMAR visual acuity by 0.76 (P=0.0516), 0.64 (P=0.0618), and 0.58 (P=0.0159), respectively. At year 3, failed amblyopia therapy, failed angle surgery, nystagmus, media opacity (MO), or ASD increased the final LogMAR by 1.30, 1.34, 1.21, 0.85, 0.64, respectively (all P<0.02). Failed angle surgery or MO increased the chance of uncontrolled IOP at the final visit (proportional odds ratio of 6.77 and 12.88, respectively).

CONCLUSIONS

In this pilot study of a modest size cohort, the presence of nystagmus, ASD or failed angle surgery early in the course of infantile-onset glaucoma management predicted poor final visual outcome, whereas failed angle surgery and presence of MO predicted poor final IOP control. These predictors of poor outcomes will serve as the initial steps in constructing a severity staging system.

Myopia: Anatomic Changes and Consequences for Its Etiology

The process of emmetropization is the adjustment of the length of the optical axis to the given optical properties of the cornea and lens after the end of the second year of life. Up to the end of the second year of life, the eye grows spherically. Axial elongation in the process of emmetropization after the second year of life is associated with a thinning of the retina and a reduced density of retinal pigment epithelium (RPE) cells in the equatorial and retroequatorial region, and a thinning of the choroid and sclera, starting at the equator and being most marked at the posterior pole. In contrast, retinal thickness and RPE density in the macular region and thickness of Bruch membrane (BM) in any region are independent of axial length. It led to the hypothesis that axial elongation occurs by the production of additional BM in the equatorial and retroequatorial region leading to a decreased RPE density and retinal thinning in that region and a more tube-like than spherical enlargement of the globe, without compromise in the density of the macular RPE cells and in macular retinal thickness. The increased disc-fovea distance in axially myopic eyes is caused by the development and enlargement of parapapillary, BM-free, gamma zone, whereas the length of macular BM, and indirectly macular RPE cell density, and macular retinal thickness, remain constant.

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.

Clinical Manifestations of Strabismus in Patients with Primary Congenital Glaucoma

Purpose: To determine the clinical manifestations and risk factors of developing strabismus in primary congenital glaucoma (PCG) patients who underwent glaucoma surgery. Methods: A retrospective case-series study of 54 PCG patients who were followed for at least 3 years after glaucoma surgery. The subjects were divided into 2 groups based on the occurrence of strabismus. Age at glaucoma diagnosis and surgery, visual acuity, intraocular pressure, amblyopia, cup-disc ratio, and orthoptic status were compared between the 2 groups. Results: Twenty of 54 patients (37.0%) developed strabismus after glaucoma surgery. The mean ages at the time of glaucoma diagnosis and surgery were 3.2 ± 2.7 months and 3.4 ± 2.8 months in the strabismus group and 24.3 ± 19.1 months and 26.4 ± 18.9 months in the non-strabismus group, respectively (p < .05). In addition, the mean logMAR visual acuities were 0.87 ± 0.38 in the strabismus group and 0.24 ± 0.21 in the non-strabismus group (p < .05). The proportion of patients experiencing amblyopia was 90.0% in the strabismus group. Low visual acuity and young age at glaucoma surgery were significant predictors of developing strabismus. Kaplan-Meier survival analysis demonstrated that the probability of developing strabismus after glaucoma surgery was 50.6% at 10 years post-surgery. Conclusions: PCG patients who developed strabismus after glaucoma surgery were diagnosed with glaucoma and underwent surgery at a younger age, exhibited a worse mean best corrected visual acuity, and exhibited a higher amblyopia incidence than did patients in the non-strabismus group.

Postoperative outcome of three different procedures for childhood glaucoma

Purpose

To investigate the long-term postoperative outcome of three surgical procedures for childhood glaucoma.

Patients and methods

In this retrospective study, the patients were divided into a goniotomy group, a trabeculotomy group, and a filtering surgery group, based on the initial surgical procedure. Failure was defined as an IOP ≥21 mmHg with medication at two consecutive visits. A Kaplan–Meier analysis was applied to calculate the probability of success. Additional metrics included IOP, number of additional operations, eye drop scores, and visual acuity.

Results

We studied 40 eyes of 25 patients, 21 eyes of 15 patients, and 12 eyes of 7 patients in the goniotomy, trabeculotomy, and filtering surgery groups, respectively. The 10- and 20-year probability of success was 65.2% and 65.2%, 42.2% and NA (no data for 20 years), and 91.7% and 80.2% for the goniotomy, trabeculotomy, and filtering surgery groups, respectively.

Conclusion

All three procedures maintained an IOP of less than 21 mmHg for up to 10 years in 65.2%, 42.2%, and 91.7% of childhood glaucoma cases.

Long-Term Visual Outcomes in Children with Primary Congenital Glaucoma

PURPOSE

To determine the long-term visual outcomes and risk factors for visual loss in children with primary congenital glaucoma (PCG) who underwent angle surgery over a 21-year period.

METHODS

This was a retrospective study of patients who underwent trabeculotomy, trabeculectomy, or combined trabeculotomy-trabeculectomy for PCG. Visual acuity (VA), surgeries, and underlying cause of visual impairment were recorded and compared. Main outcome measures were final best-corrected good VA (20/20 to 20/50), moderate VA (<20/50 to 20/200), or poor VA (<20/200); age at surgery, sex, laterality, type of initial glaucoma surgery, and number of surgeries were recorded.

RESULTS

Fifty-three eyes were eligible to be included in the study. The mean logMAR VA was 0.61 ± 0.57. A good VA was attained in 51%, moderate VA in 30%, and poor VA in 19%. The main cause of visual impairment with VA <20/50 was deprivation amblyopia (64%). There was no association between VA level and status of success (controlled with or without medications) (p = 0.202). The mean spherical equivalent of refraction was -4.47 ± 5.66; myopia was the predominant refractive error (74%) and astigmatism >2 D (40%). A statistically significant high myopic shift was more frequent in the visually impaired group. None of the studied factors was statistically associated with moderate to poor visual outcome (all p>0.05).

CONCLUSIONS

A favorable VA outcome was achieved. Topical antiglaucoma medication has an adjuvant role in maintaining the success rate of surgery without risking the visual outcome. Corneal opacification and anisometropia were the cause of amblyopia.