Diurnal Intraocular Pressure Fluctuation Research Articles

Continuous 24-hour intraocular pressure monitoring in normal Chinese adults using a novel contact lens sensor system

AimsTo investigate the physiological nyctohemeral intraocular pressure (IOP) rhythms of normal Chinese adults using a novel contact lens sensor system (CLS) that can output IOP in millimetres of mercury (mm...

Relationship between intraocular pressure fluctuation and visual field progression rates in the United Kingdom Glaucoma Treatment Study

To investigate whether intraocular pressure (IOP) fluctuation is independently associated with the rate of visual field (VF) progression in the United Kingdom Glaucoma Treatment Study. Randomized, double-masked, placebo-controlled multicenter trial. Participants with ≥5 VFs (213 placebo, 217 treatment). Associations between IOP metrics and the VF progression rates (mean deviation (MD) and five fastest locations) were assessed with linear mixed models. Fluctuation variables were mean ocular pulse amplitude (OPA), standard deviation (SD) of diurnal IOP (diurnal fluctuation), and SD of IOP at all visits (long-term fluctuation). Fluctuation values were normalized for mean IOP to make them independent from mean IOP. Correlated non-fluctuation IOP metrics (baseline, peak, mean, supine and peak phasing IOP) were combined with principal component analysis (PCA), and principal component 1 (PC1) was included as a covariate. Interactions between covariates and time from baseline modelled the effect of the variables on VF rates. IOP was measured with Goldmann applanation tonometry and OPA with Pascal tonometry. Analyses were conducted separately in the two treatment arms. Associations between IOP fluctuation metrics and rates of MD and five fastest test locations. In the placebo arm, only PC1 was significantly associated with the MD rate (estimate [standard error (SE)]: -0.19 [0.04] dB/year, p<0.001), while normalized IOP fluctuation metrics were not. No variable was significantly associated with MD rates in the treatment arm. For the fastest five locations in the placebo group, PC1 (estimate [SE]: -0.58 [0.16] dB/year, p<0.001), CCT (estimate [standard error (SE)]: 0.26 [0.10] dB/year for 10 μm thicker, p=0.01) and normalized OPA (estimate [SE]: -3.50 [1.04] dB/year, p=0.001) were associated with rates of progression; normalized diurnal and long-term IOP fluctuations were not. In the treatment group, only PC1 (estimate [SE]: -0.27 [0.12] dB/year, p=0.028) was associated with the rates of progression. There is no evidence to support that either diurnal or long-term IOP fluctuation, as measured in clinical practice, are independent factors for glaucoma progression; other aspects of IOP, including mean IOP and peak IOP, may be more informative. OPA may be an independent factor for faster glaucoma progression.

Correlation of diurnal fluctuations in intraocular pressure and progression of chronic simple glaucoma

Purpose: To study the correlation between diurnal fluctuations of intraocular pressure and progression of chronic simple glaucoma. Introduction: Out of all the risk factors for glaucoma, only modifiable risk factor is intraocular pressure. A lot of studies have been done to determine the relationship between the behavior of diurnal intraocular pressure (IOP) and progression of glaucoma. The results varied and are inconclusive because the visual field damage could have occurred at a time when the IOP was high, although it was low at the time of measurement. Materials and Methods: A prospective study was conducted on all patients diagnosed or suspected CSG with office IOP &lt;25 mmHg. Measurement of diurnal fluctuation in IOP was done by taking 2 hourly IOP readings after admitting patients in hospital for 1 day. Results: The mean baseline diurnal fluctuation of our patients was 8.5 mmHg with values reaching as high as 13.6 mmHg in some patients. 28.8% of the patients of our study group showed progression at the end of 2-year follow-up. As the baseline diurnal fluctuation increased, the number of patients showing progression increased.

Posture-related fluctuations of intraocular pressure in healthy children with suspicion of glaucoma

PurposeCurrently, there are no specific data on the circadian course of intraocular pressure (IOP) in children, especially for IOP measurements in the supine position. The study aimed to characterize the diurnal and nocturnal IOP fluctuations in supine and sitting positions in patients less than 18 years of age.MethodsSeventy-nine eyes of 79 patients under 18 years of age with suspicious optic nerve heads or ocular hypertension could be included in this study. All included patients showed an inconspicuous retinal nerve fiber layer thickness and Bruch’s membrane minimum rim width by coherence tomography. IOP measurements during the 24-h IOP profile were retrospectively evaluated. Measurements were taken at 10:00, 16:00, 20:00, and 23:00 h in the sitting position and at 6:00 h in the morning in the supine position using iCare rebound tonometry on 2 consecutive days.ResultsThirty-four of 79 children (43.0%) had peak nocturnal IOP values > 25 mmHg. The mean daily IOP was 18.8 ± 5.6 mmHg, and the mean daily fluctuation was 6.1 ± 4.0 mmHg. At 6 am, supine measurements were elevated to 25.1 ± 8.0 mmHg. Extensive fluctuations with values > 40 mmHg in the nocturnal supine measurement occurred in a relevant share of patients (n = 5).ConclusionThere appear to be relevant diurnal and nocturnal IOP fluctuations in healthy children (< 18 years). Nocturnal IOP measurements in supine patients with risk factors for glaucoma may provide important additional information to identify critical patients for further follow-up.

PRESERFLO ™ MicroShunt versus trabeculectomy: 1-year results on efficacy and safety.

To compare the efficacy and safety of the PRESERFLO™ MicroShunt versus trabeculectomy in patients with primary open-angle glaucoma (POAG) after one year. Institutional prospective interventional cohort study comparing eyes with POAG, which had received the PRESERFLO™ MicroShunt versus trabeculectomy. The MicroShunt group was matched with the trabeculectomy group for age, known duration of disease, and number and classes of intraocular pressure (IOP) lowering medications to have similar conjunctival conditions. The study is part of the Dresden Glaucoma and Treatment Study, using a uniform study design, with the same inclusion and exclusion criteria, follow-ups and standardized definitions of success and failure for both procedures. mean diurnal IOP (mdIOP, mean of 6 measurements), peak IOP, and IOP fluctuations. success rates, number of IOP lowering medications, visual acuity, visual fields, complications, surgical interventions, and adverse events. Sixty eyes of 60 patients, 30 in each group, were analyzed after 1-year follow-ups. Median [Q25, Q75] mdIOP (mmHg) dropped from 16.2 [13.8-21.5] to 10.5 [8.9-13.5] in the MicroShunt and from 17.6 [15.6-24.0] to 11.1 [9.5-12.3] in the trabeculectomy group, both without glaucoma medications. Reduction of mdIOP (P = .596), peak IOP (P = .702), and IOP fluctuations (P = .528) was not statistically significantly different between groups. The rate of interventions was statistically significantly higher in the trabeculectomy group, especially in the early postoperative period (P = .018). None of the patients experienced severe adverse events. Both procedures are equally effective and safe in lowering mdIOP, peak IOP and IOP fluctuations in patients with POAG, one year after surgery. NCT02959242.

Intracorneal Ring Segment Implantation Results in Corneal Mechanical Strengthening Visualized With Optical Coherence Elastography.

To quantify the mechanical impact of intracorneal ring segment (ICRS) implantation of different dimensions in an ex vivo eye model. A total of 30 enucleated porcine eyes were assigned to ICRS implantation (thickness: 300 µm, angle: 120°, 210°, or 325°), tunnel creation only, or virgin control groups. For mechanical evaluation, each globe was mounted on a customized holder and intraocular pressure (IOP) was increased in steps of 0.5 mm Hg from 15 to 17 mm Hg, simulating physiologic diurnal IOP fluctuations. At each step, an optical coherence tomography volume scan was recorded. Deformations between subsequent scans and the locally induced axial strains were analyzed using a vector-based phase difference method. The effective E-modulus was derived from the overall induced strain as a measure of global mechanical impact. ICRS implantation increased the effective E-modulus from 146 and 163 kPa in virgin and tunnel-only eyes to 149, 192, and 330 kPa in eyes that received a 5-mm optical zone ICRS with 120°, 210°, and 325° arc length, respectively; and to 209 kPa in a 6-mm optical zone ICRS with 325° arc length. The most consistent effect was a shift toward positive strains in the posterior stroma by 0.1% to 0.46% (factor 1.15 to 2.15) after ICRS surgery. ICRS implantation reduces the overall tissue strain under the load of the IOP and provokes posterior tissue relaxation. This effect is more prominent the longer the arc length and the smaller the optical zone of the ICRS is. ICRS have not only a geometrical, but also a mechanical impact on corneal tissue. This behavior might have clinical implications when ICRS implantation is performed in biomechanically weakened keratoconic corneas. [J Refract Surg. 2022;38(7):459-464.].

Pulsatile Trabecular Meshwork Motion: An Indicator of Intraocular Pressure Control in Primary Open-Angle Glaucoma.

(1) Background: To investigate the value of pulsatile trabecular meshwork (TM) motion in predicting the diurnal intraocular pressure (IOP) fluctuation of primary open-angle glaucoma (POAG). (2) Methods: This cross-sectional study recruited 20 normal patients and 30 patients with POAG. Of the POAG group, 20 had stable diurnal IOP and 10 had high IOP fluctuation. A clinical prototype phase-sensitive optical coherence tomography (PhS-OCT) model was used to measure TM pulsatile motion with maximum velocity (MV) and cumulative displacement (CDisp). (3) Results: MV and CDisp were higher in the external region in both normal and POAG patients. All MV and CDisp reduced significantly in the POAG group (p < 0.001). In the POAG group, except MV in the external region (p = 0.085), MV and CDisp in the nasal area were significantly higher than those in the temporal area (p < 0.05). The MV and CDisp in the external region in the nasal area of POAG patients with high IOP fluctuation were much lower than those with stable IOP (pEMV3 = 0.031, pECDisp3 < 0.001); (4) Conclusions: Pulsatile TM motion reduced in POAG patients relevant to the level of diurnal IOP fluctuation. This study presents the segmental variance of TM stiffness in human living eyes and suggests the clinical potential of the measurement of pulsatile TM motion with PhS-OCT for the evaluation of diurnal IOP fluctuation.

Two-Year Follow-up of MicroPulse Transscleral Laser Therapy in Patients with Primary Open-Angle Glaucoma.

To determine the long-term efficacy and safety of MicroPulse transscleral laser therapy (TLT) over a 24-month period in patients with primary open angle glaucoma. This prospective interventional case series evaluated data from 44 medically treated eyes of primary open angle glaucoma (POAG) patients who received MicroPulse TLT to achieve further reduction in IOP. The reduction in 24-hr mean diurnal intraocular pressure (IOP), diurnal IOP fluctuations, and peak IOP were monitored after 3, 12, and 24 months. Postoperative complications, failure rates, and factors influencing IOP reduction were also evaluated. IOP decreased from 16.1 ± 3.4 mmHg preoperatively to 13.0 ± 2.9 mmHg (n = 31; p < 0.001), 12.3 ± 3.0 mmHg (n = 27; p < 0.001), and 13.1 ± 2.6 mmHg (n = 23; p < 0.001) at the 3-month, 12-month and 24-month follow-ups. At 24months, 23 eyes (52%) had a sufficient IOP reduction to reach the individual target pressure. No severe complications were observed. No parameters could be identified that correlated with successful IOP reduction after treatment. The highest failure rate was observed during the first 3 months and remained stable thereafter. For about 50% of POAG eyes receiving the maximum tolerated treatment, MicroPulse TLT proved an effective method of further lowering IOP so as to reach the individual target pressure.

Effect of Mindfulness-Based Stress Reduction on Intraocular Pressure in Patients With Ocular Hypertension: A Randomized Control Trial

To evaluate the effect of mindfulness-based stress reduction (MBSR) on intraocular pressure (IOP) in patients with ocular hypertension (OHT). Parallel arm, single masked, randomized controlled trial. Sixty patients with ocular hypertension and IOP > 21 and < 30 mmHg were recruited at a tertiary eye care centre in India. Thirty patients (group 1) underwent six weeks of one hour daily MBSR sessions, while the other 30 patients (group 2) were waitlisted and kept on follow-up. The primary outcome was change in IOP (ΔIOP) after six weeks of MBSR. Secondary outcomes were effect on serum cortisol level, diurnal variation of IOP, vessel perfusion and vessel density on optical coherence tomography angiography (OCTA), and quality of life (QOL). At six weeks, a significant decrease in IOP was noted in group 1 (23.05 ± 1.17 to 19.15 ± 1.45 mmHg; P=.001) compared with group 2 (22.55 ± 0.98 mmHg to 22.37 ± 1.07 mmHg; P=.107). The ΔIOP was significantly greater in group 1 (3.93 ± 1.47) than group 2 (0.17 ± 0.58; P = .001). The diurnal fluctuation of IOP decreased in group 1 (4.87 ± 1.13 mmHg to 2.73 ± 0.98 mmHg; P=.001) as compared with group 2 (4.50 ± 0.86 mmHg to 4.30 ± 0.83 mmHg; P=.227). Significant improvement in vessel perfusion, vessel density, and flux index was noted on OCTA in group 1 compared with group 2. Group 1 showed a significant decrease (P ≤ .001) in serum cortisol level and an improved QOL (P=.001). Mindfulness-based stress reduction was associated with a significant decrease in IOP and serum cortisol, along with an improvement in optic nerve head perfusion and QOL. Mindfulness-based stress reduction can be considered as a potential treatment option in the management of OHT.

Intraocular pressure and diurnal fluctuation of open-angle glaucoma and ocular hypertension: a baseline report from the LiGHT China trial cohort

AimsTo report the baseline intraocular pressure (IOP) characteristics and its diurnal fluctuation in the Laser in Glaucoma and Ocular Hypertension China cohort.Methods622 primary open-angle glaucoma (POAG) patients and 149 ocular...

Efficacy of Selective Laser Trabeculoplasty on Circadian Intraocular Pressure Following Trabeculectomy in Advanced Primary Open-angle Glaucoma.

In about 50% of post-trabeculectomy (TE) eyes, selective laser trabeculoplasty (SLT) is effective in further lowering intraocular pressure (IOP). To investigate the efficacy and safety of SLT in post-TE eyes, uncontrolled on maximum tolerated medication, and/or with progression of visual field loss. This retrospective study consecutively included post-TE eyes of patients diagnosed with primary open-angle glaucoma who had been treated with 360 degrees SLT and had a follow-up after 12 months. Primary endpoints were the reduction of mean diurnal intraocular pressure (mdIOP, mean of 6 measurements), peak IOP, and diurnal IOP fluctuations. Secondary outcomes were factors influencing IOP reduction, SLT success, and failure rates. Forty-three eyes of 43 patients were included. During the first year, 10 eyes (23%) needed additional procedures to reduce mdIOP and were accounted as failures and excluded from final analysis. Of the remaining 33 eyes (77%) mdIOP [Q25, Q75] dropped from 15.2 [12.2 to 16.5] to 13.2 [11.6 to 15.3] mm Hg (P=0.027), 23 eyes (54%) showed a sufficient mdIOP reduction, 1 year after SLT. SLT is effective and safe in lowering mdIOP to target IOP in about 50% of eyes after prior incisional glaucoma surgery.

Suppression of Diurnal (9AM-4PM) IOP Fluctuations with Minimally Invasive Glaucoma Surgery: An Analysis of Data from the Prospective, Multicenter, Single-Arm GEMINI Study.

PurposeThis study analyzes diurnal IOP data (9AM, 12PM, 4PM) from a prospective 12-month trial of the OMNI Surgical System in open-angle glaucoma (OAG) patients with the aim of evaluating effect of MIGS surgery on the amplitude of the diurnal IOP profile pre- and postoperatively.SettingFifteen ophthalmology practices and surgery centers located in 14 states in the United States.DesignProspective, multicenter, IRB approved study. Patients treated with canaloplasty (360°) and trabeculotomy (180°). Patients had cataract and mild–moderate OAG with intraocular pressure (IOP) ≤33 mmHg on zero to four hypotensive medications.MethodsPost-hoc analysis of diurnal IOP data from the multicenter GEMINI study. Analysis includes comparison of IOP preoperatively and at month 12 for each of the diurnal time points, 9AM, 12PM, 4PM, change in magnitude of spread between the maximum IOP and minimum IOP for each patient and the proportions of patients preoperatively and at month 12 with IOPs at or below 25, 21, 18, and 15 mmHg, average variability (standard deviation of the 9AM, 12PM, and 4PM IOP) preoperatively and at month 12.ResultsA total of 128 patients included in this analysis. IOP at each diurnal timepoint was significantly lower postoperatively (p<0.0001). The difference between highest and lowest IOP measurement for each patient averaged 2.8 mmHg preoperatively (SD 2.4, MAX 14, MIN 0) and 1.8 mmHg (SD 1.7, MAX 10, MIN 0) month 12 (P<0.00001). The proportion with IOP ≤ to 25, 21, 18, and 15 mmHg increased; 75%–97%, 27%–88%, 1%–79%, and <1%–56%, respectively. The average variability was greater at all time points preoperatively (P<0.0001).ConclusionThis study demonstrates that eyes with OAG can benefit from an overall decreased IOP and degree of IOP fluctuations for as long as 12 months after surgical treatment with canaloplasty and trabeculotomy.

PRESERFLO™ MicroShunt versus trabeculectomy: first results on efficacy and safety.

To report efficacy and safety outcomes of the PRESERFLO™ MicroShunt compared with trabeculectomy, the current gold-standard treatment for advanced glaucoma, in the early and intermediate postoperative period. Institutional prospective interventional cohort study of primary open-angle glaucoma (POAG) patients scheduled for the PRESERFLO™ MicroShunt. The comparison group were POAG patients who had had received trabeculectomy and were matched for age, known duration of disease, number and classes of intraocular pressure (IOP)-lowering medications to ensure a similar conjunctival condition. The study is part of the Dresden Glaucoma and Treatment Study (DGTS), was not randomized, but used a uniform study design, with the same inclusion and exclusion criteria as well as standardized definitions of success and failure. mean diurnal IOP (mdIOP, mean of 6 measurements), diurnal peak IOP, diurnal IOP fluctuations, glaucoma medical therapy, success rates, visual acuity, visual fields, surgical complications and interventions, and severe adverse events. Fifty-two eyes of 52 patients, 26 in each group, were analysed. At 6 months, median [Q25, Q75] mdIOP was 10.8 [9.5-12.2] mmHg in the microshunt and 10.3 [7.6-11.8] mmHg in the trabeculectomy group. Reduction in mdIOP (p = 0.458), peak diurnal IOP (p = 0.539), and median diurnal fluctuation (p = 0.693) was not statistically significantly different between groups. The rate of interventions was statistically significantly higher in the trabeculectomy compared with the microshunt group (p = 0.004). None of the patients experienced severe adverse events. Both procedures are equally effective and safe in lowering mdIOP in patients with POAG. Because the microshunt is less invasive with less follow-up and interventions needed postoperatively, it might be recommended earlier in the treatment of glaucoma.

Comparison between Latanoprost, Travoprost, and Tafluprost in reducing intraocular pressure fluctuations in patients with glaucoma.

To compare the efficacies of latanoprost 0.005%, travoprost 0.004%, and tafluprost 0.0015% in reducing diurnal intraocular pressure (IOP) fluctuations in patients with newly diagnosed primary open-angle glaucoma (POAG). In this prospective randomized clinical trial, 60 patients who were newly diagnosed with POAG were divided into three equal groups. Patients were examined at presentation and at second and sixth weeks. Diurnal phasing of IOP was conducted using a calibrated Goldmann applanation tonometer. IOP measurements were recorded from 8:00 am to 9:00 am, from 3:00 pm to 4:00 pm, and from 7:00 pm to 8:00 pm. The study groups were distributed similarly in terms of age and gender (p-values: 0.76) and the participants had a mean age of 52.98 ± 13.43 years. The IOP at the day of inclusion was not statistically significant among the three groups (p-values 0.27, 0.51, and 0.64 at 8 am, 2 pm, and 8 pm, respectively). Similar nonsignificant differences were noticed on the follow-up visits. However, the tafluprost group showed a significant reduction in IOP on the follow-up visit at the second week at 8 pm (30.5% reduction, p-value: 0.03). All three drugs showed a comparable and significant reduction in IOP and IOP fluctuations. The pattern of side effects was similar in all the groups. Latanoprost, travoprost, and tafluprost show a similar effectiveness in reducing the mean IOP and the diurnal IOP fluctuation in POAG. Importantly, the three drugs have comparable tolerability with insignificant differences regarding the pattern of their side effects.

One-Year Follow-up of Pars Plicata Versus Pars Plana Application of Transscleral Micropulse Cyclophotocoagulation.

To compare the efficacy and safety of micropulse transscleral cyclophotocoagulation applied at the level of the pars plicata transscleral micropulse cyclophotocoagulation (PLI-MPC) versus the pars plana transscleral micropulse cyclophotocoagulation (PLA-MPC). This prospective interventional case series included 44 eyes of 31 medically treated primary open-angle glaucoma patients scheduled for micropulse transscleral cyclophotocoagulation to achieve further intraocular pressure (IOP) reduction. In total, 22 eyes underwent PLI-MPC and PLA-MPC each. Primary endpoints were the reduction of 24-hour mean diurnal IOP (mean of 6 measurements), diurnal IOP fluctuations, and peak IOP, after 3 and 12 months. Secondary outcomes were postoperative complications, a possible deterioration in visual acuity and field, factors influencing IOP reduction, and the number of dropouts. In the PLI-MPC group, IOP was reduced from 15.9±3.4 mm Hg to 13.6±3.1 mm Hg (n=16; P<0.001) and 12.9±3.7 mm Hg (n=13; P<0.001) at 3 and 12-month follow-up. In the PLA-MPC group, IOP decreased from 16.4±3.5 mm Hg to 12.3±2.6 mm Hg (n=15; P<0.001) and 11.8±2.2 mm Hg (n=14; P<0.001), respectively. At 12 months, 59% of the PLI-MPC and 63% of the PLA-MPC group had a sufficient IOP reduction to reach the individual target pressure. No complications were seen in either group. A higher preoperative IOP was recognized as the only factor influencing the postoperative IOP reduction. PLI-MPC and PLA-MPC seem to be safe and effective in further lowering the IOP in about 60% of patients with primary open-angle glaucoma who did not reach target pressure despite maximally tolerated IOP-lowering medication. Although the IOP-lowering effect was not statistically significantly different between groups the pars plicata application was superior and easier to perform and should be recommended as the preferred method of application.

Сравнительная оценка суточных кривых ВГД у пациентов с осложненной катарактой на фоне псевдоэксфолиативного синдрома до и после факоэмульсификации с имплантацией ИОЛ

Purpose. To perform a comparative analysis of the 24-hour control of intraocular pressure (IOP) amplitudes in patients with complicated cataract associated with PEX before and after phacoemulsification of cataract. Material and methods. The clinical study was carried out in 154 eyes of 154 patients with cataract associated with pseudoexfoliation syndrome (PEX). All patients diagnosed with cataract associated with PEX were divided into 3 groups: the group 1 included patients with normal IOP level preoperatively (n=55); the group 2 included patients with IOP ophthalmohypertension preoperatively (n=57); the group 3 included patients with primary open-angle initial glaucoma (n=42). The study of the amplitude of 24-hour fluctuations of IOP and diurnal curve of IOP before and after cataract phacoemulsification was performed. Before the PHACO+IOL the amplitude of diurnal IOP fluctuations was in the group 1: 5.22±0.49 mm Hg, and in the groups 2 and 3: 6.81±1.21 mmHg and 6.60±1.49 mm Hg, respectively. Results. Patients of the group 1 had a significant decrease in the amplitude of diurnal IOP fluctuations by 1.27±0.93 mm Hg (p<0.001). A decrease in the amplitude of diurnal IOP fluctuations by 2.34±1.26 mm Hg (p<0.001) was noted in patients of the group 2. In the group 3 a decrease in the amplitude of diurnal IOP fluctuations by 1.15±1.14 mm Hg (p<0.001) was observed. A tendency of changes in diurnal IOP curves after surgery was revealed in all cases. Conclusion. PHACO+IOL in patients with cataract associated with PEX allows to normalize the level, amplitude and type of diurnal IOP curve.

Diurnal Spikes of Intraocular Pressure in Uveitic Glaucoma: A 24-hour Intraocular Pressure Monitoring Study

ABSTRACT Purpose The aim of this study was to document diurnal changes in intraocular pressure (IOP) in uveitic glaucoma (UG) and compare it with primary open angle glaucoma (POAG) patients. Methods Eight patients with UG and seven patients with POAG were included in this study. The patients were matched for age, gender, and glaucoma medications. None of the patients experienced angle closure, uveitis attack, and ocular surgery, and were not under steroid or immunomodulatory therapy within the last three months. The 24-hour IOP fluctuations were recorded with the help of a contact lens sensor (Sensimed Triggerfish ®, Switzerland). The diurnal IOP fluctuations were modeled with best-fit lines and statistical comparisons between the longitudinal responses of the two groups were determined with nonlinear regression. Results The comparison of mean 24-hour contact lens sensor (CLS) amplitudes revealed a significant difference between the fluctuation levels of UG and POAG groups (213 ± 160 millivolt equivalents (mVeq) vs. 162 ± 168 mVeq, respectively p = .003). The top level of the best-fit curves was significantly higher in the UG group (266 ± 143 mVeq) compared to the POAG group (159 ± 162 mVeq, p < .001). Both curves had their top levels between 5:00 PM and 8:00 AM. The longitudinal regression analysis revealed that the amplitudes of the 24-hour fluctuation waves were significantly different (p = .041). Conclusions This study demonstrated for the first time that the diurnal variation in IOP was significantly higher in UG patients. This difference was also more distinct between 5:00 PM and 8:00 AM clock-hours. The uveitis and glaucoma specialists should consider this potential for higher IOP fluctuations, while tailoring the glaucoma treatment in uveitic patients.

Papillomacular retinoschisis associated with glaucoma

Peripapillary and macular retinoschisis is one of the rare manifestations of advanced glaucoma of different types. The article presents a case report and a mini-review. Peripapillary and macular retinoschisis with visual deterioration was diagnosed in a patient with advanced decompensated open-angle glaucoma and pseudoexfoliation syndrome. Surgical treatment of glaucoma led to intraocular pressure normalization, gradual regress of retinoschisis and improvement of visual functions. The retinal structure fully restored 1.5 years after the operation. The observation period was 3 years, retinoschisis did not recur. The article discusses the pathogenesis and potential algorithm for the treatment of the disease. Risk factors for the development of retinoschisis include high intraocular pressure, significant visual field defects and a wide range of diurnal intraocular pressure fluctuations. The source of the intra-retinal fluid is the vitreous body. Management of the patient consists of medical, laser and surgical normalization of intraocular pressure and regular monitoring. In case of persisting retinoschisis, patient undergoes vitreoretinal surgery or barrier laser coagulation. Retinal structure recovers gradually after the intervention and takes on average 1 year.

Induction of significant intraocular pressure diurnal fluctuation in rats using a modified technique of microbead occlusion.

To investigate the effect of microbead iridocorneal angle occlusion on intraocular pressure (IOP) diurnal fluctuation in rat eyes. Male Dark Agouti (DA) rats, 8-10 week old, were each given a single intracameral injection of microbeads, followed by injection of dispersive viscoelastic solution. The right eye served as the experimental eye, while the left eye served as the control. IOP was measured twice daily postoperatively for 3wk and compared between groups. At the end of 3wk, the rats were sacrificed and the eyes were harvested for histological analysis and retinal ganglion cell (RGC) counting. After microbead injection, experimental eyes had significantly higher dark time IOP than controls from the second week to the third week [2nd week: 22.92±1.631 mm Hg (n=5) vs 17.35±0.751 mm Hg (n=5); 3rd week: 23.59±1.494 mm Hg vs 17.73±0.592 mm Hg (n=5)], while light time IOP was comparable between groups. The fluctuation levels of IOP in the experimental eyes were 7.21±0.398 mm Hg (n=5), 9.50±1.017 mm Hg (n=5) and 10.66±0.894 mm Hg (n=5) from the first week to the third week after injection. Comparatively, they were significantly lower in the control eyes, which were 4.69±0.323 mm Hg (n=5), 2.84±1.122 mm Hg (n=5) and 4.98±0.603 mm Hg (n=5) respectively. However, at the end of 3wk, the larger fluctuations in IOP in the experimental eyes was not associated with a significant loss of RGCs. Microbead occlusion exacerbates diurnal IOP fluctuation in rats. This reported model may serve as a method of investigating the pathological effects of IOP fluctuation. A longer observation period, or repeated injections, may be needed to observe a significant change in RGC density.

Optical coherence tomography-measured changes over time in anterior chamber angle and diurnal intraocular pressure after laser iridotomy: IMPACT study.

The change in the anatomical dimensions over time and the effect on diurnal intraocular pressure (DIOP) following laser peripheral iridotomy is poorly understood. To evaluate change over time in anterior chamber angle anatomy following laser peripheral iridotomy (LPI) in patients with primary angle closure compared to control eyes. Additionally, the effect of LPI on DIOP fluctuation was investigated. Longitudinal, prospective, double-randomized research study. Adults with suspected angle closure or angle closure diagnosis referred to hospital services in the United Kingdom. Thirty-nine patients newly diagnosed with bilateral primary angle closure/suspects (PAC/PACS) received LPI to one eye and changes in angle morphology were measured over eight sections with swept source AS-OCT. The other eye acted as control with intraocular pressure (IOP) measured hourly. Angle opening distance (AOD), trabecular-iris angle (TIA), angle recess area (ARA), and trabecular-iris space area (TISA) at 500 and 750 μm from scleral spur. There was an increase in all angle parameters following LPI, which was maintained for 6 months (e.g. inferotemporal segment AOD500 0.041 mm (P = 0.008) at 1 week and 0.039 mm (P = 0.003) at 6 months) following LPI. Greatest effect at 6 months post-LPI was observed opposite the iridotomy site in the inferior/inferotemporal sections (AOD500 0.039 mm, P = 0.003 and AOD750 0.075 mm, P = 0.002). There were no statistically significant differences for the overall DIOP fluctuation values in the treated group at 6 months post-LPI compared to baseline. LPI widened all angle sections with maximum effect observed in the site opposite the iridotomy. Angle changes were maintained up to 6 months after LPI treatment without any statistically significant change in DIOP fluctuation.