Intraocular Pressure Characteristics of Exfoliative Glaucoma and Exfoliation Syndrome as Determined With the Water Drinking Test

Assessing the value of the water drinking test in glaucoma-a systematic review and meta-analysis

This systematic review and meta-analysis examines the relationship between intraocular pressure (IOP) parameters derived from the water drinking test (WDT) and diurnal IOP monitoring, and evaluates the reproducibility of the WDT and its association with future glaucomatous visual field (VF) loss. A literature search was performed on PubMed, EMBASE, and Cochrane Library from inception to 31 March 2023. Cohort, cross-sectional and observational studies reporting WDT results in glaucoma patients were included. Meta analysis with random-effect model was performed using "metafor" package in R version 3.2.1. 641 studies were identified on initial literature search. 38 studies (2479 subjects) were included in final analysis. Meta-analytic estimates of 5 studies (310 subjects) found strong positive correlation in peak IOP between the WDT and diurnal IOP monitoring (r = 0.92, 95% CI = 0.75, 1.08, p < 0.0001). However, there was only weak positive correlation for IOP fluctuation between both methods (r = 0.26, 95% CI = 0.06,0.47, p < 0.0001). Meta-analytic estimates of 3 studies (189 subjects) suggested a trend of the diurnal peak IOP being lower than that derived from the WDT (MD = -2.37 mmHg, 95% Limit of Agreement (LOA) =-5.58,0.84, p = 0.147). Two studies found that a higher WDT peak IOP was associated with greater future VF progression. Two studies demonstrated good reproducibility in peak IOP measurements for WDTs conducted across different days. In conclusion, there was a strong positive correlation between IOP peak measurements from the WDT and diurnal IOP monitoring in glaucoma patients. The WDT peak IOP demonstrated good reproducibility and may be associated with greater future VF progression.

LOXL1 gene polymorphisms are associated with exfoliation syndrome/exfoliation glaucoma risk: An updated meta-analysis

BACKGROUND

Single nucleotide polymorphisms (SNPs) in the gene encoding LOXL1 are risk factors for exfoliation syndrome and exfoliation glaucoma. This meta-analysis comprehensively investigated the association between LOXL1 gene polymorphisms (rs1048661, rs3825942, and rs2165241) and the risk of exfoliation syndrome/exfoliation glaucoma (XFS)/(XFG).

METHODS

All eligible case-control studies, published before August 17, 2020, were searched on Medline (Ovid), PubMed, CNKI, EMBASE, and Wanfang databases.

RESULTS

In total, 5022 cases and 8962 controls were included in this meta-analysis. Significant associations between LOXL1 gene polymorphisms and XFS/XFG risk was observed in the disease types-based subgroups. In addition, in the subgroup analysis of ethnicity, positive associations between LOXL1 gene polymorphisms (rs1048661, rs3825942, and rs2165241) and XFS/XFG risk were found in Caucasians. Furthermore, rs1048661 and rs3825942 polymorphisms were related to XFS/ XFG risk in Asians; however, no significant association was observed between the LOXL1 gene rs2165241 polymorphism and XFS/XFG risk in Asians. In addition, rs1048661 and rs3825942 correlated with XFS/XFG susceptibility in Africans.

CONCLUSIONS

Our results implicate LOXL1 gene polymorphisms as XFS/XFG risk factors, especially in Caucasians.

Correlation between intraocular pressure obtained with water drinking test versus modified diurnal tension curve measurement in pseudoexfoliation glaucoma

PURPOSE

The aim of this paper was to study the correlation and agreement between the intraocular pressure (IOP) peak value and fluctuations detected with the modified diurnal tension curve (mDTC) and the water drinking test (WDT) in pseudoexfoliation glaucoma (XFG) patients.

METHODS

This prospective observational study enrolled 42 eyes of 42 XFG patients. The IOPs were measured at 2-h intervals from 8 am to 4 pm with a Goldmann applanation tonometer by a single observer to establish the mDTC. The WDT was then performed between 4 and 5 pm on the same day and the IOP was measured 4 times at 15-min intervals after water ingestion. The IOP_peak, IOP_mean, IO _min, and IOP_fluctuation were measured with both the mDTC and WDT. The paired sample t test, Spearman's correlation coefficient and Bland-Altman plots were used for statistical analysis.

RESULTS

The mean age of the 42 patients consisting of 24 females and 18 males was 66.9 ± 6.8 years, and the mean central corneal thickness was 517.7 ± 29.1 µm. The mean values with the mDTC and WDT measurements were 15.05 ± 2.75 mmHg and 17.17 ± 3.25 mmHg (p ≤ 0.0001, r = 0.884) for IOP_mean, 16.76 ± 3.45 mmHg and 18.92 ± 3.94 mmHg (p ≤ 0.0001, r=0.787) for IOP_peak, and 13.61 ± 2.56 mmHg and 15.11 ± 2.84 mmHg (p ≤ 0.0001, r=0.824) for IOP_min, respectively, and a positive correlation was present between these values.

CONCLUSION

There was a positive correlation between the peak, minimum, and mean IOP values determined using the mDTC and WDT in treated XFG patients. WDT can be used as an alternative in the assessment of the IOP in these patients as a more practical method.

Predictive Value of the Water Drinking Test and the Risk of Glaucomatous Visual Field Progression

PURPOSE

The purpose of this is to test the hypothesis the intraocular pressure (IOP) peaks during a stress test [the water drinking test (WDT)] can estimate the risk of future visual field progression in treated primary open-angle glaucoma (POAG) patients.

PATIENTS AND METHODS

Design: Prospective, longitudinal study.

SETTING

Clinical practice.

STUDY POPULATION

Treated POAG patients whose IOP was ≤18 mm Hg and who had no IOP-lowering interventions between the date of the WDT and the last eligible visual field.

INTERVENTION

At baseline examination, patients underwent the WDT and were then followed at regular intervals with office-based IOP measurements and visual field testing.

MAIN OUTCOME MEASURE

Cox-proportional hazards survival analysis testing the predictive value of IOP peaks during the WDT versus IOP measurements during office hours on visual field progression.

RESULTS

A total of 144 eyes of 96 patients with baseline visual field damage ranging from mild to severe followed for a mean of 28 months were analyzed. In the multivariable analysis adjusting for potential confounders, higher IOP peaks during the WDT were predictive of future visual field progression (hazard ratio=1.11; 95% confidence interval, 1.02 to 1.21; P=0.013). The average and peak IOP during office hours over the same follow-up period were not significantly associated with progression (P=0.651 and 0.569, respectively).

CONCLUSIONS

IOP peaks detected with the WDT were predictive of future visual field progression in a treated POAG population. This stress test could be a useful tool for risk assessment in daily practice.

Orofacial pain and headaches associated with exfoliation glaucoma

BACKGROUND AND OVERVIEW

Exfoliation syndrome is the most common identifiable cause of open-angle glaucoma. The authors report a case of exfoliation glaucoma in a patient who had orofacial pain.

CASE DESCRIPTION

A 77-year-old woman was treated at the orofacial pain clinic for left-sided facial pain and headaches of 7 months' duration. Her cataracts and open-angle glaucoma had been diagnosed approximately 3 years earlier. Her main symptoms were orofacial pain, eye redness, inflammation of the eyelids, and eyelid edema. Magnetic resonance imaging showed no evidence of intracranial or extracranial pathology. Hemicrania continua was considered as a possible diagnosis. Indomethacin was prescribed but did not affect her headaches. She then went to an ophthalmologist to rule out secondary headaches. Intraocular pressure was 13 millimeters of mercury in the right eye and 67 mm Hg in the left eye. The ophthalmologist made a diagnosis of exfoliation glaucoma, and the patient underwent surgical treatment for the glaucoma and cataracts. After surgery, she was free of symptoms, and intraocular pressure was 15 mm Hg in the left eye.

CONCLUSIONS AND PRACTICAL IMPLICATIONS

During differential diagnosis, dentists need to consider intraoral and systemic conditions that can mimic odontogenic or orofacial pain disorders in the patient's medical history and that have a higher incidence associated with the patient's age.

Applications of the water drinking test in glaucoma management

Intraocular pressure (IOP) peaks and means have been considered important factors for glaucoma onset and progression. However, peak IOP detection depends only on appropriated IOP checks at office visits, whereas the mean IOP requires longitudinal IOP data collection and may be affected by the interval between visits. Also, IOP peak assessment is necessary to verify if the peak pressure of a given patient is in target range, to evaluate glaucoma suspect risk, the efficacy of hypotensive drugs and to detect early loss of IOP control. The water-drinking test has gained significant attention in recent years as an important tool to evaluate IOP peaks and instability. The main objective of this review was to present new findings and to discuss the applicability of the water-drinking test in glaucoma management.

Reproducibility of the water-drinking test in patients with exfoliation syndrome and exfoliative glaucoma

PURPOSE

To evaluate the reproducibility of intraocular pressure (IOP) peaks and fluctuations detected during the water-drinking test (WDT) in patients with exfoliation syndrome (XFS) and exfoliative glaucoma (XFG).

METHODS

This prospective study included 34 XFS and 30 XFG patients. Each patient was evaluated twice, with the two WDTs performed on a 30-day interval. We recorded IOP peak (highest IOP during the WDT) and IOP fluctuation (IOP peak minus IOP before the test). Bland-Altman analysis was applied to assess the agreement of IOP peaks and fluctuations between the two consecutive visits. We defined reproducible as within 4 mmHg for IOP peak and within 2 mmHg for IOP fluctuation.

RESULTS

There were no significant differences in IOP values, IOP peaks and IOP fluctuations between the two visits for both XFS and XFG patients (p > 0.05, for all). The coefficient of repeatability for IOP peak was 2.5 mmHg and 3.5 mmHg in XFS and XFG patients respectively and for IOP fluctuation, it was 2.1 mmHg and 2.2 mmHg. None of the XFS or XFG patients had an IOP peak difference higher than 4 mmHg. Intraocular pressure (IOP) fluctuation differences above 2.0 mmHg were found in 8.8% of XFS patients and 16.6% of XFG patients.

CONCLUSIONS

Intraocular pressure (IOP) peak and IOP fluctuation have a reproducibility, both in XFS and in XFG.