Pediatric glaucoma: review of recent literature

Reduced Aqueous Humor Outflow Pathway Arborization in Childhood Glaucoma Eyes

Purpose

To compare aqueous humor outflow (AHO) pathway patterns between eyes of childhood glaucoma patients and non-glaucomatous patients receiving cataract surgery.

Methods

Aqueous angiography was performed in childhood glaucoma eyes (n = 5) receiving glaucoma surgery and in pediatric (n = 1) and healthy adult (n = 5) eyes receiving cataract surgery. Indocyanine green (0.4%) was introduced into the anterior chamber, and AHO was imaged using an angiographic camera (SPECTRALIS HRA+OCT with Flex Module). Images were acquired and analyzed (ImageJ with Analyze Skeleton 2D/3D plugin) from the nasal sides of the eyes, the usual site of glaucoma angle procedures. Image analysis endpoints included AHO vessel length, maximum vessel length, number of branches, number of branch junctions, and vessel density.

Results

Qualitatively, childhood glaucoma eyes demonstrated lesser AHO pathway arborization compared to pediatric and adult eyes without glaucoma. Quantitatively, childhood glaucoma and healthy adult cataract eyes showed similar AHO pathway average branch lengths and maximum branch lengths (P = 0.49-0.99). However, childhood glaucoma eyes demonstrated fewer branches (childhood glaucoma, 198.2 ± 35.3; adult cataract, 506 ± 59.5; P = 0.002), fewer branch junctions (childhood glaucoma, 74.6 ± 13.9; adult cataract, 202 ± 41.2; P = 0.019), and lower vessel densities (childhood glaucoma, 8% ± 1.4%; adult cataract, 17% ± 2.5%; P = 0.01).

Conclusions

Childhood glaucoma patients demonstrated fewer distal AHO pathways and lesser AHO pathway arborization. These anatomical alternations may result in a new source of trabecular meshwork-independent AHO resistance in this disease cohort.

Translational Relevance

Elevated distal outflow pathway resistance due to decreased AHO pathway arborization may explain some cases of failed trabecular bypass surgery in childhood glaucoma.

The comparison of corneal densitometry in cases with glaucoma following childhood cataract surgery and juvenile glaucoma

PURPOSE

To compare the corneal densitometry (CD) in pediatric cases with glaucoma following childhood cataract surgery and juvenile open-angle glaucoma (JOAG).

METHODS

This prospective comparative study involved 13 eyes with JOAG, 12 eyes with pseudophakic glaucoma, 13 eyes with aphakic glaucoma, and 15 control subjects. Pentacam HR Scheimpflug corneal topography was employed to evaluate corneal thickness (CCT) and CD values.

RESULTS

The mean intraocular pressure (IOP) and CCT were significantly higher in aphakic glaucoma cases than the other groups (p = 0.001). In aphakic eyes, the mean CD values were higher in most of the anterior, center, and posterior layers of 0-2 mm, 2-6 mm, 6-10 mm, and total zones (p < 0.001 for all). In pseudophakic eyes, the mean CD values were statistically similar with that of aphakic eyes and higher than that of JOAG and control eyes in all layers of 0-2 mm zone and in anterior layer of 10-12 mm and anterior and total layers of 2-6 mm zones (p < 0.05 for all). The CD values demonstrated significant correlations with CCT values in both aphakic and pseudophakic eyes. However, a significant correlation of CD values with IOP was only demonstrated in aphakic eyes (p = 0.01 for all).

CONCLUSION

The probable effects of childhood cataract surgery especially aphakia might cause corneal backscatter of light and increased CD in all layers in all zones of the cornea. Increased CD values and its correlation with CCT and IOP in aphakic glaucoma eyes may be of importance in clinical management.

Current surgical techniques for the management of pediatric glaucoma: A literature review

Pediatric glaucoma surgery is challenging due to its diverse and complex pathophysiology, altered anterior segment anatomy, greater potential for failure, and complications compared to adult patients. Moreover, numerous challenges are associated with long-term postoperative management. Thus, when dealing with childhood glaucoma, it is important to consider the potential complications in addition to the benefits of each intervention. The purpose of this article is to review recently published literature to shed light on the most recent surgical techniques for the safe and effective treatment of childhood glaucoma. Current literature shows that goniotomy and trabeculotomy are the first choices for the management of primary congenital glaucoma. Although older children with phakic eyes seem to benefit from trabeculectomy with adjunctive mitomycin C, it carries a long-term risk of bleb-related endophthalmitis. Glaucoma drainage devices may be preferred for patients with secondary or refractory glaucoma. However, hypotony or tube-related complications are common and encountered more often in children than in adults. Cyclodestructive procedures are also an option for cases in which filtering surgery has failed, but they can also be used as a temporizing measure to reduce the rate of complications in high-risk patients. However, their outcomes can be unpredictable, in terms of efficiency and complications. Finally, minimally invasive glaucoma surgery (MIGS) as the sole alternative treatment or as an adjunctive surgical procedure is a relatively new path for pediatric patients.

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.

Geographic Information System Mapping of Social Risk Factors and Patient Outcomes of Pediatric Glaucoma

PURPOSE

This study aimed to use Geographic Information System (GIS) mapping to present the geospatial distribution of visual outcomes and sociodemographic risk factors of a cohort of pediatric glaucoma patients.

DESIGN

Retrospective cohort study.

SUBJECTS

233 eyes of 177 pediatric glaucoma patients treated at UC Davis Medical Center.

METHODS

We reviewed the medical records of pediatric patients (aged less than 18 years) with the diagnosis of pediatric glaucoma or any adult with a prior history of pediatric glaucoma at UC Davis Medical Center from 2001 to 2019. Patient sociodemographic information and ocular health data were recorded. Patients were mapped to their residential home 3-digit zip code prefix using ArcGIS software to generate geographic representations of the pediatric glaucoma database. Statistical analyses were performed to identify significant risk factors to poor visual outcome.

MAIN OUTCOME MEASURES

The primary outcome was the patient's final visual acuity (VA), defined as a binary variable based on the World Health Organization's criteria: good VA (better than 20/200) or poor VA (worse than 20/200). The secondary outcome was final intraocular pressure (IOP) at patients' final follow-ups. Risk factors for poor vision and higher IOP were assessed.

RESULTS

At final follow-up, 65 eyes (27.9%) had poor vision and 168 eyes (72.1%) had good vision. In the multivariate analysis, the odds ratio of good VA decreased by 4% for every 1 mmHg increase in initial IOP (P = 0.03), and the odds of good VA decreased by 6% for every year increase in age (P = 0.04). Patients with private insurance had a 3.5 mmHg lower final IOP than those with Medicaid (P = 0.004). Travel distance was not associated with a poorer visual outcome.

CONCLUSIONS

Private insurance patients had lower final IOP than Medicaid patients. Age and initial IOP were significant negative predictors of VA. Despite travel distance appearing to be associated with poorer visual outcomes by GIS mapping, it was not statistically significant. Geographic information system mapping of patient outcomes is an innovative way to visualize patient demographics and risk factors. Geographic information system may prove particularly useful in larger nationwide disease and surgical registries, especially for rare disorders like pediatric glaucoma.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found after the references.

Intraocular Pressure Measurement in Childhood Glaucoma under Standardized General Anaesthesia: The Prospective EyeBIS Study

Objective: We aimed to compare intraocular pressure (IOP) measurements using iCare® PRO rebound tonometry (iCare) and Perkins applanation tonometry (Perkins) in childhood glaucoma subjects and healthy children and the influence of anaesthesia depth, age and corneal thickness. Material: Prospective clinical, case-control study of children who underwent an ophthalmologic examination under general anaesthesia according to our protocol. Children were 45.45 ± 29.76 months old (mean ± SD (standard deviation)). Of all children, 54.05% were female. IOP was taken three times (T1−T3), according to duration and the depth of anaesthesia. The order of measurement alternated, starting with iCare. Agreement between the device measurements was evaluated using Bland−Altman analysis. Results: 53 glaucoma subjects and 22 healthy controls. Glaucoma subjects: IOP measured with iCare was at T1: 27.2 (18.1−33.8), T2: 21.6 (14.8−30.6), T3: 20.4 mmHg (14.5−27.0) and Perkins 17.5 (12.0−23.0), 15.5 (10.5−20.5), 15.0 mmHg (10.5−21.0) (median ± IQR (interquartile range)). Healthy controls: IOP with iCare: T1: 13.3 (11.1−17.0), T2: 10.6 (8.1−12.4), T3: 9.6 mmHg (7.7−11.7) and Perkins 10.3 (8.0−12.0), 7.0 (5.5−10.5), 7.0 mmHg (5.5−8.5) (median ± IQR). The median IOP was statistically significantly higher with iCare than with Perkins (p < 0.001) in both groups. The mean difference (iCare and Perkins) was 6.0 ± 6.1 mmHg for T1−T3, 7.3 at T1, 6.0 at T2, 4.9 mmHg at T3. Conclusion: The IOP was the highest in glaucoma subjects and healthy children at T1 (under sedation), independently of the measurement method. iCare always leads to higher IOP compared to Perkins in glaucoma and healthy subjects, regardless of the duration of anesthesia.

Minimally invasive glaucoma surgery in childhood glaucoma

PURPOSE OF REVIEW

Minimally invasive glaucoma surgery (MIGS) has been shown to be safe and effective in treatment of mild to moderate glaucoma in adults, but reports in childhood glaucoma are limited. We review the available data concerning MIGS and discuss its potential role in childhood glaucoma management.

RECENT FINDINGS

Ab interno counterparts to circumferential ab externo trabeculotomy such as gonioscopy-assisted transluminal trabeculotomy (GATT) and Trab360 show promise in treatment of primary glaucomas as reported in a few retrospective case series. Kahook Dual Blade (KDB) and Trabectome have demonstrated mixed results in few published case reports in children. Small case series and reports suggest that the Xen gel stent can be a safer alternative to traditional filtration surgery, though data on long-term implant and bleb stability are unavailable. Newer devices are being investigated and early results are encouraging.

SUMMARY

GATT and Trab360 seem to be safe, effective methods of achieving circumferential trabeculotomy in childhood glaucoma. KDB, Trabectome, and Xen gel stent have shown some success in selected cases with short-term follow-up. Surgeons must determine the risks and benefits of MIGS over more established methods of intraocular pressure reduction for each individual child. Further research is needed to validate initial findings regarding MIGS in childhood 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.

Aniridic glaucoma: An update

Aniridia is a congenital bilateral ocular disorder with dominant autosomal inheritance. More than 50% of patients will develop aniridic glaucoma (AG) during their lives. Open angle glaucoma is more common in aniridia, but a closed angle mechanism has been described in relation with anterior rotation of the rudimentary iris, occluding trabecular meshwork. Diagnosis and follow-up of AG is difficult in relation with the presence of keratopathy, nystagmus and foveal hypoplasia. Central corneal thickness usually measures more than 600 microns, which prevents achieving a reliable value of intraocular pressure. Medical treatment of AG is no different from the rest of glaucoma. It is recommended to use preservative free formulations, and combined therapy is often required. Surgical treatment is needed in many cases. There is no consensus on the first line surgery for AG, but in open angle AG, angle surgery is usually first choice, and glaucoma drainage devices are the next preferred surgical technique. In closed angle AG glaucoma drainage devices are usually the first choice, with trabeculectomy as the second preferred surgical technique.

Postoperative Changes in Central Corneal Thickness and Intraocular Pressure in a Prospective Cohort of Congenital Cataract Patients

PURPOSE

To evaluate changes in central corneal thickness (CCT) and intraocular pressure (IOP) in children after surgery for congenital cataracts and to investigate the association between CCT and IOP.

METHODS

For this prospective observational cohort study, we recruited patients undergoing surgery for unilateral or bilateral congenital cataracts. CCT and IOP were measured before surgery and 1, 3, 6, 12, and 24 months after surgery.

RESULTS

Seventy-six children (152 eyes) were enrolled; 33 eyes were unaffected by cataracts, 77 were aphakic, and 42 were pseudophakic. In aphakic eyes, mean CCT increased by 31.14 ± 44.32 μm at 12 months postoperation and 33.09 ± 35.42 μm at 24 months postoperation; this increase was significantly higher than that in pseudophakic eyes 12 months after surgery (8.36 ± 19.91 μm; P < 0.001) and 24 months after surgery (0.31 ± 14.19 μm; P = 0.024). However, no significant differences in IOP were found between the different phakic states at 12 and 24 months postoperation (P = 0.672 and P = 0.080, respectively). There were also no significant differences in CCT and IOP before and after surgery in the unaffected eyes.

CONCLUSIONS

Mean CCT peaked at 12 months, and the mean IOP remained normal in both the aphakic and pseudophakic eyes during this study. CCT and IOP were positively correlated, regardless of the phakic status or age, a relationship which suggests that both parameters should be monitored closely in postsurgical patients for up to 12 months and in this time, may impact the ability to diagnose glaucoma.

Falsely high rebound tonometry

BACKGROUND

Rebound tonometry (RBT) can be used to measure intraocular pressure (IOP) in children unable to tolerate measurement with applanation tonometry (AT) while awake. RBT readings are often 2-3 mm Hg higher than AT. We have experienced children with a repeatedly higher difference between RBT and AT measurements (≥6 mm Hg). The purpose of this study was to identify demographic and ocular characteristics that contribute to this artifactuous discrepancy.

METHODS

The medical records of pediatric patients with IOP measured by RBT followed by AT within 6 months without intervening surgery or change in medical management were retrospectively reviewed to identify potential predictors of greater difference between RBT and AT readings.

RESULTS

A total of 123 eyes of 65 patients were included. In patients with normal IOP (≤24 mm Hg), 18.5% had a ≥6 mm Hg difference between RBT and AT, with RBT being higher. Risk factors for this included presence of persistent fetal vasculature (PFV), increased corneal diameter, and higher initial RBT value (>20). In patients with elevated IOP (>24 mm Hg), 77% had ≥6 mm Hg difference, with larger corneal diameter being the sole predictor. Eyes were less likely to have significant RBT-AT difference if there was corneal opacity or iris abnormalities in eyes with elevated IOP (>24 mm Hg).

CONCLUSIONS

In some children, RBT readings are ≥ 6 mm Hg higher than AT readings. Caution should be taken when interpreting RBT values in patients with PFV, increased corneal diameter, and higher initial RBT values.

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.

Aniridic glaucoma: An update

Aniridia is a congenital bilateral ocular disorder with dominant autosomal inheritance. More than 50% of patients will develop aniridic glaucoma (AG) during their lives. Open angle glaucoma is more common in aniridia, but a closed angle mechanism has been described in relation with anterior rotation of the rudimentary iris, occluding trabecular meshwork. Diagnosis and follow-up of AG is difficult in relation with the presence of keratopathy, nystagmus and foveal hypoplasia. Central corneal thickness usually measures more than 600 microns, which prevents achieving a reliable value of intraocular pressure. Medical treatment of AG is not different from the rest of glaucoma. It is recommended to use preservative free formulations, and combined therapy is often required. Surgical treatment is needed in many cases. There is no consensus on the first line surgery for AG, but in open angle AG, angle surgery is usually first choice, and glaucoma drainage devices are the next preferred surgical technique. In closed angle AG glaucoma drainage devices are usually the first choice, with trabeculectomy as the second preferred surgical technique.

Risk Factors for Glaucoma Drainage Device Failure and Complication in the Pediatric Population

PURPOSE

Report factors associated with failure and complication in a cohort of children who have undergone glaucoma drainage device (GDD) implantation.

DESIGN

Retrospective case series.

PARTICIPANTS

Consecutive pediatric GDD eyes that met criteria between May 1997 and July 2019.

METHODS

Entries were included for analysis if age <18 years at the time of GDD implantation. Failure was defined as an intraocular pressure (IOP) greater than 21 mmHg or IOP reduction <20% or IOP <5 mmHg at 2 consecutive follow-up visits >3 months after implantation, reoperation for glaucoma, or loss of light perception vision. Complications were defined as postoperative events due to the GDD that required additional examination under anesthesia or additional surgery.

MAIN OUTCOME MEASURES

Survival analyses of surgical failures and complications.

RESULTS

Over a mean follow-up period of 5.4 years, 58 (38%) of 150 first-time GDD implants failed. Glaucoma associated with acquired conditions had decreased risk for failure when compared with glaucoma secondary to nonacquired systemic diseases (hazard ratio [HR], 12; P = 0.0063), nonacquired ocular anomalies (HR, 12; P = 0.0054), and primary congenital glaucoma (HR, 5.4; P = 0.041). There was an increased risk of failure for first-time tubes in younger patients with a 23% reduction of failure with each 3-year increase in age (HR, 0.77; P = 0.034). A total of 38 (25.3%) of the first-time GDD implantations had a complication. Higher preoperative IOP (5 mmHg increase; HR, 1.2; P = 0.038) and younger age (<3 years; HR, 2.1; P = 0.024; < 2 years, HR, 1.9; P = 0.046) increased the risk of complication. There were 22 second-time GDD implants in the study, of which 11 failed (50%), and increased risk for failure was associated with younger age at the time of implantation (<1 year; HR, 27; P = 0.0053) and concurrent glaucoma-related procedures with or without non-glaucoma anterior segment surgery at the time of implantation (HR, 13; P = 0.0085).

CONCLUSIONS

Although GDD implantation in children is relatively safe and effective, these data should be interpreted in the context of children's relative longevity. These findings offer an outcome metric to which future novel glaucoma procedures in children can be compared.

Effect of general anaesthesia on intraocular pressure in paediatric patients: a systematic review

OBJECTIVES

Assessment of the impact of general anaesthetic agents on intraocular pressure (IOP) in children via systematic review.

METHODS

Pubmed, Embase, and CENTRAL databases were systematically searched to identify randomised controlled trials, prospective, and interventional studies. The search included all studies through October 5, 2018 with no date or language restrictions. A linear mixed-effects regression analysis was performed to study the change in IOP after general anaesthesia (GA).

RESULTS

The strategy identified 518 studies that met search criteria. Six studies (531 eyes) were included for quantitative synthesis. Seven categories of mixed and non-mixed induction and maintenance agents were compared. When assessing all agents utilising a model of mean IOP as a function of time, IOP decreased after induction phase at a rate of -0.59 ± 0.19 mmHg/min (P value = 0.006).

CONCLUSIONS

This systematic review showed that most anaesthetic agents significantly decrease IOP over time after the induction phase of general anaesthesia in children. An understanding of the effects of GA on IOP is critical for those performing paediatric ophthalmic examinations under anaesthesia.

Combined Viscodilation of Schlemm's Canal and Collector Channels and 360° Ab-Interno Trabeculotomy for Congenital Glaucoma Associated with Sturge-Weber Syndrome

Purpose

This case report demonstrates the potential role of the OMNI surgical system in the surgical management of congenital glaucoma.

Patients and Methods

The case was a 4-month-old full-term, otherwise healthy female infant with cutaneous hemangiomas of both upper lids, corneal edema in the right eye (RE) and IOP > 30 mmHg. Sturge-Weber syndrome (SWS) was diagnosed. The RE was surgically treated with ab-interno circumferential viscodilation and trabeculotomy.

Results

Through 10 months of follow-up, intraocular pressure was adequately controlled without the need for adjunctive medical therapy.

Conclusion

Given its advantages over other angle surgery techniques, this procedure's role in treating glaucomas of childhood warrants further evaluation.

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.

Steroid-induced glaucoma: Epidemiology, pathophysiology, and clinical management

Glucocorticoids are a class of anti-inflammatory drugs commonly used to treat various ocular and systemic conditions. Although the role of glucocorticoids in the treatment of numerous serious inflammatory diseases is pivotal, their prolonged use may increase intraocular pressure resulting in steroid-induced glaucoma. We provide a detailed update on steroid-induced glaucoma as a preventable cause of blindness in the adult and pediatric population and describe its epidemiology, social impact, and risk factors. Furthermore, we explore the propensity of different steroids to increase the intraocular pressure, the role of different routes of steroid administration, dosage and duration of treatment, as well as the clinical features, genetics, and management of steroid-induced glaucoma.

Intermediate-term outcomes of Aurolab aqueous drainage implant in refractory paediatric glaucoma

Aim

To report the intermediate-term outcomes of Aurolab aqueous drainage implant (AADI) surgery in paediatric eyes with refractory glaucoma.

Methods

Case records of patients below 18 years, who underwent AADI surgery between 2012 and 2015 with >2 years follow-up, were analysed. The intraocular pressure (IOP), visual acuity, number of antiglaucoma medications, complications and resurgery if any were recorded at baseline, day 1and then at months 1, 3, 6, 9, 12, 18, 24 and at the last visit. Failure was defined as IOP >18 mm Hg or not reduced by at least 30% below baseline, IOP ≤5 mm Hg on two consecutive follow-up visits after 3 months, reoperation for a complication or loss of light perception vision.

Results

101 eyes of 101 patients were included with a mean age of 10.4±4.7 years at the time of surgery and a mean follow-up of 40.9±15.1 months. Glaucoma following cataract surgery was the most common type of glaucoma (n=31, 30%), followed by primary congenital glaucoma (n=29, 29%). The cumulative probability of failure was 15.8% (95% CI 10.1% to 24.5%) at 1 year, 22.7% (95% CI 15.7% to 32.2%) at 2 years, 42.5% (95% CI 32.6% to 53.9%) at 3 years and 62.1% (95% CI 49.5% to 74.8%) at the 4 years time point.

Conclusion

The AADI showed excellent success until 2 years after surgery in paediatric eyes after which failure rates increased. Further prospective studies with longer follow-up are required to evaluate the long-term success of the AADI for paediatric glaucomas.

Modified Goldmann prism intraocular pressure measurement accuracy and correlation to corneal biomechanical metrics: multicentre randomised clinical trial

PURPOSE

Clinically evaluate intraocular pressure (IOP) measurements taken with a Goldmann applanation tonometer (GAT) prism and a modified surface Goldmann prism examining measurement differences correlated to central corneal thickness (CCT) and corneal hysteresis (CH) values.

DESIGN

Prospective, open-label, randomised, controlled, multicentre reference device accuracy analysis.

METHODS

A GAT and a modified surface GAT prism measured IOP on 243 unique eyes. The study design and methodology complied with International Standard Organization (ISO) tonometer evaluation guidelines, except the inclusion of thin (<500 µm) and thick (>600 µm) corneas. All eyes were randomised to IOP measurement by one of five standard Goldmann prisms and five modified prisms. Pressures were measured by six investigators, two times with each prism for a total of 1936 IOP measurements. Analysis included a multiple linear regression including CCT and CH correlation.

RESULTS

The difference in IOP measurements of the standard and modified Goldmann prisms correlated well to CCT particularly in thin (<500 µm) and thick (>600 µm) corneas (R²=0.404, p=0.007). Corneal hysteresis (CH) also significantly correlated to the difference in prism measurements (R²=0.125, p=0.039). There was no significant overall mean IOP bias between the two prisms (+0.43 mm Hg in modified, p=0.19).

DISCUSSION

The paired IOP measurement difference between GAT and a modified surface Goldmann replacement prism indicated a statistically significant correlation to CCT and CH. A simple modified replacement prism for any Goldmann-type tonometer may significantly improve IOP measurement accuracy by minimising corneal biomechanical errors associated with CCT and CH.

TRIAL REGISTRATION NUMBER

NCT02990169 and NCT02989909.

Intraocular Pressure Measurement Accuracy and Repeatability of a Modified Goldmann Prism: Multicenter Randomized Clinical Trial

PURPOSE

To clinically evaluate a modified surface Goldmann applanation tomometer (GAT) prism for intraocular pressure (IOP) accuracy, repeatability, and safety.

DESIGN

Prospective, open-label, randomized, controlled, multicenter reference device reliability and validity analysis.

METHODS

A GAT and a modified surface GAT prism measured IOP on 173 unique eyes. The study design and analysis complied with FDA 510(k) and ANSIZ80.10-2014 guidelines. All eyes were randomized to IOP measurement by 1 of 5 standard prisms or 5 modified prisms, each from a different manufacturing lot. Pressures were measured by 6 investigators, 2 times with each prism, for a total of 1384 IOP measurements. Analysis included Bland-Altman difference accuracy, intraoperator and interoperator IOP measurement, and manufactured lot repeatability.

RESULTS

Bland-Altman indicated no IOP measurements pairs outside the ±5 mm Hg guidelines. Operator and manufactured lot repeatability F tests and 1-way ANOVAs indicated no statistical difference between the standard and modified prisms (all P > .10). The difference in IOP measurements of the standard and modified prisms correlated well to Dresdner central corneal thickness (CCT) correction (P = .01).

CONCLUSION

A modified surface replacement prism is statistically equivalent to a flat-surfaced prism. The modified surface prism indicated statistically significant correction for CCT requiring further testing outside the ANSI standard limits (0.500 mm < CCT < 0.600 mm) to examine its full potential.