Juvenile Open Angle Glaucoma Patients Research Articles

Age, Sex, and Clinical Characteristics of Juvenile Open-Angle Glaucoma Patients in a Saudi Tertiary Hospital: A Retrospective Study of Surgical and Non-Surgical Outcomes

Background/Objectives: Juvenile Open Angle Glaucoma (JOAG) is a condition that presents peculiar issues because it starts at a very early age and, in the end, causes substantial vision loss. This study aimed to analyze the age and gender distribution and treatment outcomes in JOAG patients. Methods: We carried out a retrospective study at King Abdul Aziz University Hospital, Riyadh, Saudi Arabia, from 2015 to 2022. We extracted data from the medical records. Visual acuity data were converted to the logarithm of the minimum angle resolution (LogMAR) for standardized analysis. The CARL ZEISS Humphrey 745i Field Analyzer/HFA II-i Visual Field Analyzer was used to perform visual field examinations under the 24-2 program SITA standard. Results: The study involved 45 JOAG patients (87 affected eyes) with a mean age of 26.91 years. Myopia was the prevailing trait (93%), and a family history of glaucoma was found in 51.1% of cases. Most of the patients presented with severe visual field defects in both eyes (right—57.1%, left—44.4%). Regarding visual acuity, we found that the majority of affected categories belonged to either mild or moderate in both eyes. Initial and final Intraocular pressure (IOP) measurements together showed a significant reduction (p < 0.001) and clearly demonstrated the need for IOP control. Surgical and non-surgical treatments significantly reduced IOP, with no gender or eye differences Conclusions: This research offers important data concerning JOAG demographics (age and gender), clinical picture, and treatment results. Though early-onset presents challenges, multidimensional therapeutic methods have great potential to get JOAG under control and maintain visual function. Additional research is needed to study the genetic causes of JOAG and assess the long-term treatment outcomes.

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

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. 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, 1500µm and 3000µm nasal and temporal to the foveal center, and in the peripapillary region at 6 locations: up to 1500µm, 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. The average macular ChT in JOAG was 306.30 ± 56.49µm vs. 277.12 ± 64.68µm in controls. The average peripapillary ChT in JOAG was 197.79 ± 44.05µm vs. 187.24 ± 38.89µm in controls. The average total ChT (p = 0.042), the average macular ChT (p = 0.022), the subfoveal ChT (p = 0.022), the ChT 1500µm (p < 0.001), and 3000µm 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. In this South Asian cohort of JOAG, the average total ChT, average macular ChT, subfoveal ChT, and ChT at 1500µm, and 3000µm temporal to the fovea were significantly thicker when compared to healthy controls.

Selective laser trabeculoplasty in the treatment of juvenile open angle glaucoma patients under 25years of age.

To retrospectively evaluate the effectiveness and reliability of selective laser trabeculoplasty (SLT) treatment in juvenile open angle glaucoma (JOAG) cases. The 46 eyes of 28 cases that had undergone SLT for JOAG and had a follow-up of at least one month were included in the study. The pre-SLT, month 1, month 6, year 1, year 2, and final follow-up intraocular pressure (IOP); the number of drugs before and after the SLT procedure; and the complications caused by the SLT were recorded. An IOP below 21mmHg without any additional medication or glaucoma surgery and an IOP decrease of 20% or more compared to the baseline were considered successful. There were 18 females and 10 males with a mean age of 17.52 ± 2.7 (13-22) years. The cases were followed-up for a mean duration of 39 (5-59) months. The mean IOP was 23.93 ± 0.52mmHg before SLT and decreased to 17.15 ± 0.57mmHg at month 1 after the procedure, 17.17 ± 0.52mmHg at month 6, 18.02 ± 0.77mmHg at year 1, 18.12 ± 0.48mmHg at year 2, and 20.93 ± 0.69mmHg at the final follow-up. The post-SLT IOP measurements at all times were found to be significantly lower than the pre-SLT values (p < 0.001). The mean number of drugs was 1.5 before the SLT and 0.59 afterwards (p < 0.001). The most common complications after SLT were anterior chamber inflammation in 29 cases (63.04%), hyperemia in 20 (43.40%) cases (4.34%), an early period IOP increase of 5mmHg or more in 11 cases (23.91%), and mild ocular pain in 2 cases (4.34%). SLT is an effective and reliable method for JOAG treatment.

Treatment Outcomes for Juvenile Open-Angle Glaucoma in Thailand.

Juvenile open-angle glaucoma patients with thick central corneas and negative family history were more likely to undergo surgery, mainly trabeculectomy with half requiring additional surgery within 10 years. To assess the characteristics and treatment outcomes of patients with juvenile open-angle glaucoma (JOAG) in Thailand. This retrospective, multicenter study included all patients diagnosed with JOAG over 12 years from two tertiary hospitals in Bangkok, Thailand. A total of 200 eyes from 104 patients were included in this study. The mean age of onset was 24.0±10.1 years (range 5-40), with male predominance (60.5%). Over 90% of patients had bilateral JOAG and 25% had a positive family history. Negative family history (AOR=4.59, P=0.02) and thick central corneal thickness (CCT) were surgical predictors (every 10 micron AOR=1.29, P=0.01). Over 70% of cases needed glaucoma surgery. Trabeculectomy with Mitomycin-C was performed on 131 eyes (65.5%) with a cumulative probability of complete success of 71.0%, 57.8%, 39.2%, and 26.9% and qualified success of 86.3%, 73.6%, 64.8%, and 45.7% at 1, 3, 5, and 10 years, respectively. Mean follow-up after surgery was 94.9 ± 69.8 months (range 13-153). There were no serious post-operative complications. Myopia and number of baseline glaucoma medications were significantly associated with surgical failure. Trabeculectomy with Mitomycin C was the most common primary surgery performed in Thai patients with JOAG, and successfully reduced intraocular pressure without significant complications. Patients with thicker corneas were more likely to undergo surgery. By 10 years, half of the patients required additional surgery and risk factors for failure included myopia and the number of medications.

Mutations in EFEMP1 in Patients with Juvenile Open-Angle Glaucoma

Determine the role of the EFEMP1 gene in the pathogenesis of juvenile open-angle glaucoma (JOAG). Prospective case-control PARTICIPANTS: 72 JOAG and 215 POAG patients and 362 controls from Iowa. DNA was tested for coding sequence mutations in the EFEMP1gene using Sanger or whole exome sequencing. No non-synonymous EFEMP1 mutations were detected in JOAG patients and one non-synonymous EFEMP1variant (c.146A>C, p.Asp49Ala) was detected in both POAG patients (n= 2, 1.5%) and controls (n=4, 1.1%) at similar frequencies (p = 0.67). EFEMP1 mutations are not a common cause of glaucoma in our cohort from Iowa.

Glaucoma Cascade Screening in a High Risk Afro-Caribbean Haitian Population: A Pilot Study.

Précis:Glaucoma cascade screening in first-degree relatives (FDRs) of young Haitian glaucoma patients had high yield for diagnosing manifest and suspected glaucoma in 30.8% of those screened despite modest participation.Purpose:To evaluate the outcomes of glaucoma cascade screening in FDRs (parents, siblings, and offspring) of Haitian juvenile open-angle glaucoma (JOAG) patients.Patients and Methods:Consecutive index patients (Haitians with JOAG) were identified, and the number/type of FDRs residing in South Florida were recorded. These FDRs were invited for free glaucoma screening, which included a comprehensive ophthalmic exam, gonioscopy, automated visual field testing and optical coherence tomographic analysis of the retinal nerve fiber layers. FDR characteristics and clinical findings from screening are reported.Results:A total of 77 FDRs were invited, 26 (33.8%) agreed to undergo screening (18 females, 9 males), which revealed 2 (7.7%) with manifest glaucoma (mean age 77.5 y; one of whom was previously unaware of his glaucoma diagnosis), 6 (23.1%) with suspected glaucoma (mean age 29.8±18.3 y), and 18 (69.2%) without manifest or suspected glaucoma (mean age 37.2±21.8 y). Siblings of index patients were least likely to participate in cascade glaucoma screening when compared with index patients’ parents or offspring. FDR eyes with manifest glaucoma had significantly worse best-corrected visual acuities, higher intraocular pressures, thinner central corneal thicknesses, and thinner circumferential papillary retinal nerve fiber layer thicknesses than those without glaucoma.Conclusion:Glaucoma cascade screening of Haitian JOAG patients’ FDRs revealed that 30.8% had suspected or manifest glaucoma. Future efforts centered on provider-initiated recruitment and improving public glaucoma awareness and education may increase screening participation.

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.

Intermediate Outcomes of Deep Sclerectomy in Juvenile Glaucoma.

In this retrospective study of patients with predominantly severe juvenile open-angle glaucoma, deep sclerectomy (DS) achieved a success rate [defined as intraocular pressure (IOP) between 5 to 18 mm Hg] of 72% at 3 years. The purpose of this study was to evaluate the safety and efficacy of DS in patients with juvenile open-angle glaucoma (JOAG). A retrospective chart review of all JOAG patients that underwent DS with mitomycin C at a tertiary care eye center during the period from May 2014 to May 2019. A total of 50 eyes in 37 patients were included. The mean age at the time of surgery was 27.1±11.3 years and the majority of patients (86%) had a cup-disc ratio of 0.8 to 0.9. The mean duration of follow-up was 26.1±13.4 months (range 12 to 54 mo). Mean IOP was reduced from 26.1±13.4 mm Hg at baseline to 15.2±6.4 mm Hg at the last follow-up visit (P<0.01). Moreover, the mean number of glaucoma medications decreased from 3.8±0.5 at baseline to 0.8±1.2 at the last follow-up visit (P<0.01). The cumulative probabilities of overall success (defined as IOP between 5 and 18 mm Hg) at 12, 24, and 36 months were 94%, 85%, and 72%, respectively. Hypotony occurred in 4 eyes (8%), and in one of these patients, the final visual acuity was >2 lines worse compared with presentation. No other vision-threatening complications were encountered. DS in JOAG was safe and successfully controlled IOP in most patients for 3 years.

EFEMP1 rare variants cause familial juvenile-onset open-angle glaucoma.

Juvenile open-angle glaucoma (JOAG) is a severe type of glaucoma with onset before age 40 and dominant inheritance. Using exome sequencing we identified 3 independent families from the Philippines with novel EFEMP1 variants (c.238A>T, p.Asn80Tyr; c.1480T>C, p.Ter494Glnext*29; and c.1429C>T, p.Arg477Cys) co-segregating with disease. Affected variant carriers (N = 34) exhibited severe disease with average age of onset of 16 years and with 76% developing blindness. To investigate functional effects, we transfected COS7 cells with vectors expressing the three novel EFEMP1 variants and showed that all three variants found in JOAG patients caused significant intracellular protein aggregation and retention compared to wild type and also compared to EFEMP1 variants associated with other ocular phenotypes including an early-onset form of macular degeneration, Malattia Leventinese/Doyne's Honeycomb retinal dystrophy. These results suggest that rare EFEMP1 coding variants can cause JOAG through a mechanism involving protein aggregation and retention, and that the extent of intracellular retention correlates with disease phenotype. This is the first report of EFEMP1 variants causing JOAG, expanding the EFEMP1 disease spectrum. Our results suggest that EFEMP1 mutations appear to be a relatively common cause of JOAG in Filipino families, an ethnically diverse population.

Myopia and glaucoma progression among patients with juvenile onset open angle glaucoma: A retrospective follow up study.

To identify the risk factors for glaucoma progression, especially the association with myopia, among treated juvenile open angle glaucoma (JOAG) patients. Glaucomatous progression was analysed in the eyes of JOAG patients with at least 5-years of follow up in this retrospective study. Baseline variables such as age, inheritance pattern, baseline intraocular pressure (IOP), baseline central corneal thickness, visual acuity, baseline refractive error, spherical equivalent (SE) and duration of follow-up were noted. Stereoparametric global trend analysis and Moorfields Regression Analysis on confocal scanning laser ophthalmoscopy were used to detect progression. Variables associated with glaucoma progression, with respect to progressors (PG) and non-progressors (NPG) were analysed. Since both eyes of a patient were taken for analysis, a generalised estimating equation method was used to correct the bias. Among 74 eyes (37 subjects), glaucoma progression was noted in 11 eyes (14.9%) of 8 patients, with a median time to progression of 7.4years (range 5-15.5years). For myopes (SE≤-1.00D), glaucoma progression was 18 times more likely than mild and no myopes (>-1DS) (p=0.03, 95% CI: 1.14, 217.44). The prevalence of myopia in the JOAG, PG and NPG cohorts was 70.3%, 87.5%, and 65.5%, respectively. Myopia progression was noted at follow up in 70% patients. One-unit increase in baseline vertical cup disc ratio, 1mmHg increase in IOP fluctuations and 1dB year-1 depression of visual field were associated with 0.44, 0.06 and 0.07D year-1 increases in the rate of myopia progression, respectively. JOAG progressors had a greater baseline myopic refraction and a faster myopia development over time. The development of myopia in JOAG eyes could be an indicator of glaucoma progression, and hence progressing myopic (≤-1D) JOAG patients should be followed up more rigorously.

Optical coherence tomography angiography in juvenile open angle glaucoma: correlation between structure and perfusion.

Juvenile open angle glaucoma (JOAG) is a type of glaucoma that occurs in patients younger than 40years. Only a few studies have assessed vascular perfusion in JOAG and correlated it with structural damage. The aim of this study is to investigate vascular perfusion in JOAG by optical coherence tomography angiography (OCTA) and correlate it with structural damage, represented by retinal nerve fiber layer (RNFL) thinning. This is a cross-sectional observational study of 25 eyes of patients with JOAG. All patients underwent full ocular examination and scanning by OCTA to measure parameters such as RNFL thickness, peripapillary and disk vascular density. Average superior and inferior RNFL thicknesses were 69.4 (± 22.1) and 70.4 (± 25.6) μm, whereas peripapillary and disk vascular densities were 38.2(± 10), and 39.1(± 12) % and superior and inferior vascular densities were 38.1(± 10.5) and 38.2(± 9.7) %. A strong positive correlation was found between the superior and inferior RNFL thickness and the vascular density of the peripapillary region, the disk and the superior and inferior vascular densities (p < 0.001 for all). OCTA parameters are strongly correlated with structural damage in JOAG patients. OCTA can serve as a helpful tool in the diagnosis and assessment of progression in JOAG and be utilized as a prognostic indicator, thus filling the defects and gaps present in other methods of assessment.

The effect of trabeculectomy combined with prophylactic sclerotomy as a treatment of late stage juvenile open angle glaucoma and primary congenital glaucoma patients: a primary observational study

Objective: To evaluate the outcomes of trabeculectomy combined with a new prophylactic sclerotomy in late stage juvenile open angle glaucoma (JOAG) and primary congenital glaucoma (PCG) patients at high risks of intraoperative and postoperative suprachoroidal hemorrhage (SCH). Method: A retrospective case series study. Thirty-three eyes of 28 JOAG patients and 15 eyes of 12 PCG patients with high risk factors for severe choroidal effusion or SCH were enrolled from November 2006 to April 2012 at Eye and ENT Hospital of Fudan University. The standard trabeculectomy accompanied by prophylactic sclerotomy was performed (video attached). Ophthalmic examinations were performed before and after the surgery. Surgical outcome was assessed in terms of intraocular pressure (IOP), best-corrected visual acuity, optic nerve head cup disc ratio, visual field, and complications. All patients were followed up for at least 1 year. Complete success was defined as an IOP ≥6 mmHg (1 mmHg=0.133 kPa) but ≤18 mmHg without medication. Qualified success was defined as an IOP ≥6 mmHg but ≤18 mmHg with local application of medications. Kaplan-Meier survival curves were drawn for the success rate calculation. Results: The mean age of all 40 patients was (13.2±9.4) years old. And among them, 22 patients were male and 18 patients were female. The mean follow-up time was (31.8±15.9) months. At the postoperative 3(rd) year, the complete success rate was 75.8%, and the qualified success rate was 90.0%. In our case series, one eye had expulsive SCH intraoperatively and two eyes had delayed SCH postoperatively. All of them were successfully saved without further surgery and with no significant damage to visual function. Conclusion: Trabeculectomy combined with prophylactic sclerotomy is a promising technique developed to control IOP in late stage JOAG and PCG patients, which provides a potential intervention to reduce severe consequences of massive choroidal effusion or SCH. (Chin J Ophthalmol, 2019, 55: 347-354).

A recurrent G367R mutation in MYOC associated with juvenile open angle glaucoma in a large Chinese family.

To identify the mutations of MYOC, OPTN, CYP1B1 and WDR36 in a large Chinese family affected by juvenile open angle glaucoma (JOAG). Of 114 members of one family were recruited in this study. Blood samples from twelve members of this pedigree were collected for further research. As a control, 100 unrelated subjects were recruited from the same hospital. The exon and flanking intron sequences of candidate genes were amplified using the polymerase chain reaction and direct DNA sequencing. The proband (III:10) was a seventy-three years old woman with binocular JOAG at the age of 31. A recurrent heterozygous mutation (c.1099G>A) of MYOC was identified in the three JOAG patients and another suspect. This transition was located in the first base pair of codon 367 (GGA>AGA) in exon 3 of MYOC and was predicted to be a missense substitution of glycine to arginine (p.G367R) in myocilin. Mutations in OPTN, CYP1B1 or WDR36 were not detected in this study. The G367R mutation was not present in unaffected family members or in 100 ethnically matched controls. Other variants of the coding regions of candidate genes were not detected in all participants. To date, this family was the largest to have been identified as carrying a certain MYOC mutation in China, further evidence of a founder effect for the G367R MYOC mutant was provided by our data. A MYOC c.1099G>A mutation in an autosomal dominant JOAG family is identified and the characteristic phenotypes among the patients are summarized. Genetic testing could be utilized in high-risk populations and be helpful not only for genetic counseling, but also for early diagnosis and treatment of affected patients or carriers of inherited JOAG.

Outcomes of trabeculectomy in juvenile open angle glaucoma

Purpose:This study was aimed at reporting the outcomes of trabeculectomy in primary juvenile open angle glaucoma (JOAG).Design:This study was a retrospective noncomparative case series.Materials and Methods:We included 60 eyes of 41 JOAG patients who underwent primary trabeculectomy without mitomycin-C (MMC) between 1995 and 2007. The primary outcome was success, defined as complete, if intraocular pressure (IOP) was >5 and ≤21 mmHg without medications or qualified if IOP was >5 and ≤21 mmHg with or without antiglaucoma medications. Secondary outcome measures were mean and percentage IOP reduction, complications, and risk factors for the failure of trabeculectomy.Results:The mean (±standard deviation) age at presentation was 24.1 ± 6.8 years (range, 12–35). Mean follow-up was 67 ± 41 months (range, 12–156). At 1 year, the probability of complete success was 92% (n = 56, 95% CI: 81–96%), at 3 years it was 89% (n = 47, 95% CI: 78–95%), and at the end of 5 years, it was 80% (n = 34, 95% CI: 65–89%). The probability of qualified success was 100% (n = 60) at 1 year, 98% (n = 51, 95% CI: 87–100%) at 3 years, and 96% (n = 36, 95% CI: 84–99%) at the end of 5 years. The mean IOP reduced from 35 ± 10 to 13 ± 2.5 mmHg (P < 0.001) after trabeculectomy. There was no serious postoperative complication. Young age was the only significant risk factor associated with the failure (odds ratio = 0.89, P = 0.03).Conclusion:Primary trabeculectomy without MMC has good success rates in JOAG.

Mutation spectrum of the CYP1B1 gene for congenital glaucoma in the Japanese population

Mutations of the CYP1B1 gene cause primary congenital glaucoma (PCG), Peters anomaly, and juvenile open-angle glaucoma (JOAG). The aim of this study was to determine the spectrum and role of the CYP1B1 gene in Japanese patients with PCG or JOAG. Genomic DNA was extracted from the leukocytes of 18 unrelated patients with PCG and 21 unrelated patients with JOAG. All of the patients developed high intraocular pressure (IOP) before the age of 35 years. One hundred unrelated healthy adults with normal IOP were examined in the same way. The three exons of the CYP1B1 gene were amplified by polymerase chain reaction and directly sequenced. Mutational screening and sequence analyses of the CYP1B1 gene revealed four mutations in four patients with PCG: p.Asp192Val, c.4776insAT, p.Val364Met, and p.Asp430Glu. The first three mutations have been reported in other Japanese PCG patients, but Asp430Glu is a new mutation. No mutations were found in the CYP1B1 gene of the JOAG patients. PCG in approximately 20% of Japanese patients may be associated with CYP1B1 mutations, but JOAG is not. The three mutations p.Asp192Val, c.4776insAT, and p.Val364Met appear to be common in the Japanese population and might be useful in genetic screening for PCG.

Large Diurnal Variation of Intraocular Pressure Despite Maximal Medical Treatment in Juvenile Open Angle Glaucoma

To report the clinical significance of large fluctuations in intraocular pressure (IOP) and the effect of trabeculectomy on diurnal IOP variations in 2 cases of maximally medically treated juvenile open angle glaucoma (JOAG). A 24-hour IOP monitoring was performed before and after trabeculectomy on both eyes of 2 JOAG patients-one with transiently blurred vision early in the morning, the other with progression of visual field defect despite apparently well-controlled IOP. The patients' optic discs were scanned with Heidelberg retina tomograph (HRT) during peak and trough IOPs before trabeculectomy. Preoperatively, diurnal IOP varied widely up to 20/19 (OD/OS) mm Hg in case 1 and up to 16/22 (OD/OS) mm Hg in case 2, even though both patients were using 4 different types of antiglaucoma eye drops. Peak IOP was associated with temporary blurring of vision and mild corneal edema in 1 patient (case 1). Heidelberg retina tomograph revealed a deepening of the optic cup and a resultant narrowing of the neuroretinal rim at peak IOP in this patient; this was not detected in the second patient who had tilted optic discs. After trabeculectomy, diurnal IOP fluctuations were reduced to 4-6/2-4 (OD/OS) mm Hg in case 1 and to 6-7/3-7 (OD/OS) mm Hg in case 2, with a decrease in peak IOPs as well. Wide diurnal variation should be suspected in JOAG patients, even when receiving maximal medical treatment; this is especially important in cases with temporary blurred vision and/or progression of visual field defect despite apparently well-controlled IOP. Trabeculectomy was more effective in reducing diurnal IOP variation than medical treatment.