Clinical correlates to the goniodysgensis among juvenile-onset primary open-angle glaucoma patients

Choroidal thickness in juvenile open angle glaucoma: insights from a south asian case-control study

PURPOSE

The purpose of this study is to compare choroidal thickness in juvenile open angle glaucoma (JOAG) and healthy controls using spectral domain optical coherence tomography (SD-OCT) and study its correlations.

METHODS

In this case-control study, 56 eyes of 28 JOAG patients and an equal number of controls were recruited. SD-OCT was used to measure the choroidal thickness (ChT), in the macular region at 5 locations: subfoveal, 1500 µm and 3000 µm nasal and temporal to the foveal center, and in the peripapillary region at 6 locations: up to 1500 µm, nasal and temporal to the disc, respectively. The ChT and its correlations with age, intraocular pressure, cup-to-disc ratio, central corneal thickness, mean deviation, and axial length were studied.

RESULTS

The average macular ChT in JOAG was 306.30 ± 56.49 µm vs. 277.12 ± 64.68 µm in controls. The average peripapillary ChT in JOAG was 197.79 ± 44.05 µm vs. 187.24 ± 38.89 µm in controls. The average total ChT (p = 0.042), the average macular ChT (p = 0.022), the subfoveal ChT (p = 0.022), the ChT 1500 µm (p < 0.001), and 3000 µm temporal to the fovea (p = 0.002) were significantly thicker in the JOAG group. In the JOAG group, the average macular ChT had a significant negative correlation with age, whereas axial length was positively correlated with the average peripapillary ChT.

CONCLUSIONS

In this South Asian cohort of JOAG, the average total ChT, average macular ChT, subfoveal ChT, and ChT at 1500 µm, and 3000 µm temporal to the fovea were significantly thicker when compared to healthy controls.

Machine learning-assisted prediction of trabeculectomy outcomes among patients of juvenile glaucoma by using 5-year follow-up data

OBJECTIVE

To develop machine learning (ML) models, using pre and intraoperative surgical parameters, for predicting trabeculectomy outcomes in the eyes of patients with juvenile-onset primary open-angle glaucoma (JOAG) undergoing primary surgery.

SUBJECTS

The study included 207 JOAG patients from a single center who met the following criteria: diagnosed between 10 and 40 years of age, with an IOP of >22 mmHg in the eyes on two or more occasions, open angle on gonioscopy in both eyes, with glaucomatous optic neuropathy, and requiring a trabeculectomy for IOP control. Only the patients with a minimum 5-year follow-up after surgery were included in the study.

METHODS

A successful surgical outcome was defined as IOP ≤18 mmHg (criterion A) or 50% reduction in IOP from baseline (criterion B) 5 years after trabeculectomy. Feature selection techniques were used to select the most important contributory parameters, and tenfold cross-validation was used to evaluate model performance. The ML models were evaluated, compared, and prioritized based on their accuracy, sensitivity, specificity, Matthew correlation coefficient (MCC) index, and mean area under the receiver operating characteristic curve (AUROC). The prioritized models were further optimized by tuning the hyperparameters, and feature contributions were evaluated. In addition, an unbiased relationship analysis among the parameters was performed for clinical utility.

RESULTS

Age at diagnosis, preoperative baseline IOP, duration of preoperative medical treatment, Tenon's thickness, scleral fistulation technique, and intraoperative mitomycin C (MMC) use, were identified as the main contributing parameters for developing efficient models. The three models developed for a consensus-based outcome to predict trabeculectomy success showed an accuracy of >86%, sensitivity of >90%, and specificity of >74%, using tenfold cross-validation. The use of intraoperative MMC and a punch for scleral fistulation compared to the traditional excision with scissors were significantly associated with long-term success of trabeculectomy.

CONCLUSION

Optimizing surgical parameters by using these ML models might reduce surgical failures associated with trabeculectomy and provide more realistic expectations regarding surgical outcomes in young patients.

The Increased Burden of Rare Variants in Four Matrix Metalloproteinase-Related Genes in Childhood Glaucoma Suggests a Complex Genetic Inheritance of the Disease

Childhood glaucoma encompasses congenital and juvenile primary glaucoma, which are heterogeneous, uncommon, and irreversible optic neuropathies leading to visual impairment with a poorly understood genetic basis. Our goal was to identify gene variants associated with these glaucoma types by assessing the mutational burden in 76 matrix metalloproteinase-related genes. We studied 101 childhood glaucoma patients with no identified monogenic alterations using next-generation sequencing. Gene expression was assessed through immunohistochemistry. Functional analysis of selected gene variants was conducted in cultured cells and in zebrafish. Patients presented a higher proportion of rare variants in four metalloproteinase-related genes, including CPAMD8 and ADAMTSL4, compared to controls. ADAMTSL4 protein expression was observed in the anterior segment of both the adult human and zebrafish larvae's eye, including tissues associated with glaucoma. In HEK-293T cells, expression of four ADAMTSL4 variants identified in this study showed that two variants (p.Arg774Trp and p.Arg98Trp) accumulated intracellularly, inducing endoplasmic reticulum stress. Additionally, overexpressing these ADAMTSL4 variants in zebrafish embryos confirmed partial loss-of-function effects for p.Ser719Leu and p.Arg1083His. Double heterozygous functional suppression of adamtsl4 and cpamd8 zebrafish orthologs resulted in reduced volume of both the anterior eye chamber and lens within the chamber, supporting a genetic interaction between these genes. Our findings suggest that accumulation of partial functional defects in matrix metalloproteinase-related genes may contribute to increased susceptibility to early-onset glaucoma and provide further evidence supporting the notion of a complex genetic inheritance pattern underlying the disease.

'Microincisional trabeculectomy for glaucoma"

PURPOSE

To evaluate the short-term clinical outcomes of microincisional trabeculectomy (MIT), a new technique of ab-interno trabeculectomy.

METHODS

Consecutive patients with open-angle glaucoma identified from the hospital database that underwent MIT with or without cataract surgery between September 2021 to June 2022 at a tertiary eye centre in East India, were screened. Those with a follow-up of < 6 months or with incomplete data were excluded. MIT was done ab-interno using microscissors and microforceps in 2-4 clock hours of the nasal angle via a temporal incision. The intraocular pressure (IOP) reduction at 6 months, and reduction in the number of medications after surgery were analysed. Surgical success (IOP>6 and <22 mm Hg), complications, angle features on anterior segment optical coherence tomography (ASOCT), and the need for additional surgeries were analysed.

RESULTS

We included thirty-two eyes of 32 patients with open-angle glaucoma (including n = 9 eyes that underwent concurrent cataract surgery) with a preoperative mean IOP of 22 ±11.1 mm Hg and visual field index of 47±37.9%. All eyes achieved >30% IOP reduction, with a final IOP of 14±6.9 mm Hg at 6 months. Surgical success in 31 of 32 eyes with complete success seen in 28 eyes with none of the eyes requiring >1 medication for IOP control. Hyphema was seen in 4 eyes, while transient IOP spikes at 1 day-1 month were seen in 5 eyes, none of which required any additional interventions. One eye with persistent raised IOP at 1 month required incisional trabeculectomy for uncontrolled IOP with 2 medications.

CONCLUSION

MIT, a new technique of ab-interno trabeculectomy, is effective in terms of IOP control and reduction in the number of medications while having fewer complications. Long-term studies comparing the efficacy of MIT with incisional trabeculectomy, or other procedures are warranted in the future.

The Changing Face of the Cornea in a Case of Juvenile Glaucoma and Subclinical Keratoconus

We report on a 23-year-old man who presented with bilateral subclinical keratoconus and juvenile glaucoma (JG). With intraocular pressures (IOPs) of 30 and 28 mmHg, both eyes were consecutively operated by adjusted trabeculotomy, leading to a remarkable decrease in IOP to well below the mean for this surgery in JG. Meanwhile, most keratoconus indices clearly progressed in the first 5 months postoperatively, with increases in corneal hysteresis, associated with a remarkable drop in the corneal resistance factor. During the following years, IOP remained low, and all changes (except the increase in corneal hysteresis) reverted to near preoperative levels through the follow-up course of 5 years. This report complements a few existing reports that show the coincidence of keratoconus and JG, and, more importantly, documents a novel pattern of remarkable and prolonged corneal changes following surgical lowering of IOP in eyes with these changes. Postoperative biomechanical disturbances in the cornea and possibly limbus are proposed in cases of JG and subclinical keratoconus.

Juvenile-onset open-angle glaucoma - A clinical and genetic update

Juvenile-onset open-angle glaucoma (JOAG) is a subset of primary open-angle glaucoma that is diagnosed before 40 years of age. The disease may be familial or non-familial, with proportions varying among different populations. Myocilin mutations are the most commonly associated. JOAG is characterized by high intraocular pressures (IOP), with many patients needing surgery. The mean age at diagnosis is in the 3rd decade, with a male preponderance. Myopia is a common association. The pathophysiology underlying the disease is immaturity of the conventional outflow pathways, which may or may not be observed on gonioscopy and anterior segment optical coherence tomography. The unique optic nerve head features include large discs with deep, steep cupping associated with high IOP-induced damage. Progression rates among JOAG patients are comparable to adult primary glaucomas, but as the disease affects younger patients, the projected disability from this disease is higher. Early diagnosis, prompt management, and life-long monitoring play an important role in preventing disease progression. Gene-based therapies currently under investigation offer future hope.

In Vivo Imaging of the Schlemm's Canal and the Response to Selective Laser Trabeculoplasty

OBJECTIVE

To evaluate the presence of angle dysgenesis on ASOCT (anterior segment optical coherence tomography) (ADoA) as a predictive factor in determining outcomes of selective laser trabeculoplasty (SLT).

DESIGN

A prospective clinical cohort study.

SUBJECTS

Patients with juvenile-onset open-angle glaucoma (JOAG) without angle dysgenesis on gonioscopy.

METHOD

JOAG patients with uncontrolled intraocular pressure (IOP), who were to undergo SLT, were evaluated for the presence or absence of ADoA, which was defined as the absence of Schlemm's canal (SC) and/or presence of a hyperreflective membrane (HM) over the trabecular meshwork, as identified on ASOCT before the SLT procedure. Furthermore, the number of ASOCT B-scans in which SC was identified as present, were then quantified. Success of SLT was defined as a reduction of IOP by 20% or more from pre-laser value at 6-month follow-up without any further IOP-lowering medication or surgery. Only 1 repeat SLT was admissible for defining SLT success over the 6-month period. A successful reduction in IOP at 6-month follow-up was correlated with the extent of ADoA.

RESULTS

In comparison to pre-SLT IOP, 57.1% eyes (20/35) showed more than 20% reduction in IOP at 6 months with a mean reduction of 7.6 ± 1.8 mm Hg (29.6%). When all 3 observers agreed, SC was identified in 90% eyes (18/20) with success vs 26.6% eyes (4/15) with failure (P < .001). All eyes (5/5) with presence of HM showed failure (P < .001). All eyes (19/19) in which SC was present in >50% ASOCT B scans (>25/50 scans/eye) showed success (P < .001). On a bias-reduced regression analysis, the identification of SC on any 2 consecutive scans increased the chances of success at 6 months by 8.3 times, whereas the identification of SC in >50% of ASOCT scans was associated with a 21.4 times greater chance of success.

CONCLUSIONS

The presence of SC on ASOCT is a strong predictor for successful IOP reduction after SLT in JOAG eyes.

Comparison of anterior chamber angle parameters and iris structure of juvenile open-angle glaucoma and pigmentary glaucoma

Purpose:

To compare the quantitative measurements of the anterior chamber angle (ACA) and iris parameters in patients with juvenile open-angle glaucoma (JOAG), pigmentary glaucoma (PG), and healthy controls using anterior segment optical coherence tomography (AS-OCT).

Methods:

This was a retrospective, cross-sectional study of 25 eyes with JOAG, 25 eyes with PG, and 25 control eyes. Anterior chamber depth, angle-opening distance 500 and 750, trabecular–iris space 500 and 750, scleral spur angle, iris thickness (IT, measured at the thickest part), and iris bowing were obtained using AS-OCT (Visante” OCT 3.0 Model 1000, Carl Zeiss Meditec, Inc).

Results:

The quantitative ACA parameters were found to be significantly higher in JOAG and PG patients compared to healthy controls (P < 0.001); there was no significant difference between the eyes with JOAG and PG (P > 0.05). In eyes with JOAG and PG, there was significantly backward bowing of the iris in temporal and nasal angles compared to control subjects (P < 0.001). Median iris bowing was not significantly different between the patients with JOAG and PG (P > 0.05). The temporal and nasal angle iris thickness were significantly thinner in eyes with JOAG than the eyes with PG (P < 0.001) and age-matched control subjects (P < 0.001). The median IT did not differ between the patients with PG and control subjects (P > 0.05). In patients with JOAG, the intraocular pressure (IOP) was inversely correlated with IT (r = -0.43, P < 0.05).

Conclusion:

AS-OCT provided quantitative data on the ACA and iris parameters in JOAG and PG. The evaluation of the ACA and iris structures using AS-OCT revealed higher ACA measurements and posterior bowing of the iris in patients with JOAG and PG. Furthermore, the patients with JOAG were found to have thinner IT than the ones with PG and healthy controls.

Juvenile Open-angle Glaucoma With Waardenburg Syndrome: A Case Report

Waardenburg syndrome (WS) is a genetic disorder resulting in anomalies of derivatives of neural crest cells during development. Patients tend to have variable degrees of pigmentary defects affecting skin, hair, and irides in addition to hearing loss and possible systemic neurological associations. Elevation of the intraocular pressure has been reported in several adult patients with WS. We report the first case of WS to be associated with juvenile open-angle glaucoma in a 20-year-old Egyptian man thus expanding the spectrum of the types of glaucoma that can coexist with the syndrome.

Outcomes of adjusted trabeculotomy in cases with juvenile glaucoma

PURPOSE

To evaluate surgical and visual outcomes of modified adjusted trabeculotomy in juvenile glaucoma (JG) cases.

METHODS

A retrospective case series; medical records of 43 patients (69 eyes) JG cases operated by adjusted trabeculotomy between 2011 and 2018. Those who completed a minimum of 1 year of regular follow-up, and up to 5 years were included in the study. Intraocular pressure (IOP), number of medications, cup/disc ratio (CDR), and visual acuity (VA) at baseline, postoperative 1, 3, 5 years were evaluated. Success required IOP ≤ 18 mmHg and a minimum of 20% reduction, without medications (full), or with medications (qualified).

RESULTS

Numbers of patients (eyes) who completed 1, 3, and 5 follow-up years were as follows: 26 (43), 15 (27), and 11 (19). Median (range) age at surgery was 21.5 (8-43) years. Mean (range) IOP was significantly (P < .001) reduced from 23.4 ± 8.8 (11.0-46.0) mmHg to 11.5 ± 3.5 (7.0-28.0), 10.9 ± 3.6 (6.0-24.0), and 11.4 ± 3.0 (7.0-17.0) mmHg at 1, 3, and 5 years, with reduction of medication scores. At years 1, 3, and 5, complete success rates were 89.5%, 86.8%, and 89.5%, and qualified success rates were 97.4%, 94.7%, and 97.4%. Median (range) LogMAR VA significantly (P < .001) improved from 0.3 (0-2.8) to 0.17 (0-2.8) and 0.17 (0-2.8) at 1 and 5 years. Median (range) CDR was significantly (P < .001) reduced from 0.85 (0.3-1.0) to 0.85 (0.1-1.0), 0.7 (0.05-1.0), and 0.7 (0.05-0.9) at 1, 3, and 5 years.

CONCLUSIONS

Adjusted trabeculotomy could effect remarkable IOP lowering for up to 5 years postoperatively in JG eyes, and seems to be an effective, low-risk surgical modality for treating such eyes. It can be associated with cupping reversibility, and visual improvement on the long-term. Good surgical technique and postoperative care are imperative to achieve a successful outcome.

Classifying juvenile onset primary open angle glaucoma using cluster analysis

Aim

To classify unrelated patients with juvenile onset primary open angle glaucoma (JOAG) into clinically useful phenotypes using cluster analysis.

Methods

Out of the 527 unrelated patients with JOAG, the study included 414 patients who had all the phenotypic characteristics required for the study. A cluster analysis was performed to classify the patients based on their iris and angle morphology, age of onset, highest untreated intraocular pressure (IOP), worst mean deviation and greatest vertical cup disc ratio of the worst eye. The iris features were broadly classified into three groups: those with normal iris crypts (NIC), those with prominent iris crypts (PIC) and those with absence of iris crypts. The gonio photographs were graded as normal appearing angle or those with angle dysgenesis in the form of a featureless angle, one with a high iris insertion and an angle with prominent iris processes. Using a hierarchical clustering model and a two-way cluster analysis, the distribution of clusters of JOAG was analysed to obtain a classification of JOAG subtypes.

Results

The four major clusters identified were: Cluster 1 with NIC and normal angles had the lowest untreated IOP and higher age of onset among all clusters. Cluster 2 with NIC and featureless angle was found to be associated with earliest age of onset. Cluster 3 had NIC and either a high iris insertion or prominent iris processes. Cluster 4 was a heterogeneous cluster with maximum number of patients in a group comprising of those with PIC and high iris insertion.

Conclusions

Cluster analysis extracted four subgroups of the JOAG phenotype that have clinical and prognostic significance and can potentially be helpful while evaluating these patients in the clinics.

Phenotypic differences between familial versus non-familial Juvenile onset open angle glaucoma patients

AIM

To evaluate phenotypic differences among familial and non-familial JOAG patients.

METHODS

First degree relatives of unrelated JOAG patients were screened for glaucoma and ocular hypertension. JOAG probands were grouped as familial or non-familial and phenotypic differences in terms of age of onset, gender, baseline untreated IOP, presence angle dysgenesis, and refractive error was compared between the two groups.

RESULTS

Out of 368 unrelated JOAG patients, 134 in whom all first degree relatives had been examined were included in the study. The non-familial JOAG (n = 96) had similar age of onset as familial JOAG (n = 38); (p = 0.076) but had greater male preponderance (p = 0.046), and had the higher baseline IOP (p = 0.044) compared to familial JOAG. However, on adjustment using the Bonferroni correction, the observed differences were not found to be significant. Both groups had similar proportion of patients with angle dysgenesis (p = 0.46) and high myopia (p = 0.72).

CONCLUSIONS

Non-familial JOAG were not found to be phenotypically different from the familial JOAG patients in this cohort.