Remyelination-oriented clemastine treatment attenuates neuropathies of optic nerve and retina in glaucoma.

As one of the top causes of blindness worldwide, glaucoma leads to diverse optic neuropathies such as degeneration of retinal ganglion cells (RGCs). It is widely accepted that the level of intraocular pressure (IOP) is a major risk factor in human glaucoma, and reduction of IOP level is the principally most well-known method to prevent cell death of RGCs. However, clinical studies show that lowering IOP fails to prevent RGC degeneration in the progression of glaucoma. Thus, a comprehensive understanding of glaucoma pathological process is required for developing new therapeutic strategies. In this study, we provide functional and histological evidence showing that optic nerve defects occurred before retina damage in an ocular hypertension glaucoma mouse model, in which oligodendroglial lineage cells were responsible for the subsequent neuropathology. By treatment with clemastine, an Food and Drug Administration (FDA)-approved first-generation antihistamine medicine, we demonstrate that the optic nerve and retina damages were attenuated via promoting oligodendrocyte precursor cell (OPC) differentiation and enhancing remyelination. Taken together, our results reveal the timeline of the optic neuropathies in glaucoma and highlight the potential role of oligodendroglial lineage cells playing in its treatment. Clemastine may be used in future clinical applications for demyelination-associated glaucoma.

Matched case-control comparison of surgical success after XEN45 Gel Stent and PRESERFLO MicroShunt implantation in a Caucasian population.

BACKGROUND: The aim of this study was to compare the outcome of implantation of a XEN45 Gel Stent with the outcome of implantation of a Preserflo MicroShunt in a matched-pair analysis in eyes being naïve to filtering surgery. METHODS: In this comparative, retrospective study, 50 eyes that had undergone XEN45 Gel Stent implantation were compared with 50 eyes after Preserflo implantation. Follow-up was at least 6 months, and surgical success was measured by criteria A (IOP < 21 mmHg, IOP reduction >20%, no repeat surgery); criteria B (IOP < 18 mmHg, IOP reduction >20%, no repeat surgery); and criteria C (IOP ≤15 mmHg, IOP reduction ≥40%, no repeat surgery). RESULTS: After a follow-up period of 12 months, mean IOP had decreased from preoperative 25.2 ± 4.8 mmHg in the XEN group to 14.5 ± 4.0 (n = 35) and from 25.3 ± 6.8 mmHg to 11.9 ± 2.9 (n = 41) in the Preserflo group, respectively. The IOP at the last follow-up of the two groups differed significantly (p < 0.01). The probability of surgical success did not differ concerning Criteria A and B, but surgical success was significantly higher in the Preserflo group for Criteria C (60%, p < 0.01). CONCLUSION: Both the Preserflo and XEN45 Gel Stent provide an effective and safe treatment option for advanced glaucoma and have a high potential to reduce intraocular pressure. Absolute IOP levels of <16 mmHg after 12 months were significantly more frequent in the Preserflo group.

Tau modulation through AAV9 therapy augments Akt/Erk survival signalling in glaucoma mitigating the retinal degenerative phenotype.

The microtubule-associated protein Tau is a key player in various neurodegenerative conditions, including Alzheimer's disease (AD) and Tauopathies, where its hyperphosphorylation disrupts neuronal microtubular lattice stability. Glaucoma, a neurodegenerative disorder affecting the retina, leads to irreversible vision loss by damaging retinal ganglion cells and the optic nerve, often associated with increased intraocular pressure. Prior studies have indicated Tau expression and phosphorylation alterations in the retina in both AD and glaucoma, yet the causative or downstream nature of Tau protein changes in these pathologies remains unclear. This study investigates the impact of Tau protein modulation on retinal neurons under normal and experimental glaucoma conditions. Employing AAV9-mediated gene therapy for Tau overexpression and knockdown, both manipulations were found to adversely affect retinal structural and functional measures as well as neuroprotective Akt/Erk survival signalling in healthy conditions. In the experimental glaucoma model, Tau overexpression intensified inner retinal degeneration, while Tau silencing provided significant protection against these degenerative changes. These findings underscore the critical role of endogenous Tau protein levels in preserving retinal integrity and emphasize the therapeutic potential of targeting Tau in glaucoma pathology.

Comparing the intraocular pressure values obtained with a rebound tonometer (TONOVET Plus) and an indentation tonometer (IOPvet) in dogs with and without ocular disease.

BACKGROUND: This study aimed to compare the intraocular pressure (IOP) values obtained from two groups of dogs using the IOPvet indentation tonometer to those obtained from the same dogs using an established rebound tonometer (TONOVET Plus). METHODS: Tonometry was performed on 36 dogs with ocular diseases (70 eyes; group A) and 25 healthy dogs (49 eyes; group B). First, the TONOVET Plus rebound tonometer was used. Then, one drop of oxybuprocaine hydrochloride was applied to each eye, and 1 minute later, the IOP was estimated using the IOPvet. RESULTS: The IOPvet was safe, well tolerated and easy to use. The instrument had a high specificity (98.5%) for identifying IOPs of 20 mmHg or less. A lack of sensitivity (67.9%) was noted when evaluating eyes with an IOP between 20 and 30 mmHg. The sensitivity (33.3%) for identifying canine eyes with an IOP of greater than 30 mmHg (n = 24) was low. LIMITATIONS: This study lacks manometric work, which would be hard to justify with client-owned dogs. Quantitative numerical data were compared with qualitative values and the same investigator obtained readings using both tonometers without being masked. CONCLUSIONS: The IOPvet is highly sensitive for assessing normal IOPs, but underestimation of higher IOPs can lead to poor diagnostics. Digital tonometers remain the best way to assess IOP in veterinary clinics.

The Association of Urinary Sodium Excretion with Glaucoma and Related Traits in a Large United Kingdom Population.

OBJECTIVE: Excessive dietary sodium intake has known adverse effects on intravascular fluid volume and systemic blood pressure, which may influence intraocular pressure (IOP) and glaucoma risk. This study aimed to assess the association of urinary sodium excretion, a biomarker of dietary intake, with glaucoma and related traits, and to determine whether this relationship is modified by genetic susceptibility to disease. DESIGN: Cross-sectional observational and gene-environment interaction analyses in the population-based UK Biobank study. PARTICIPANTS: Up to 103 634 individuals (mean age 57 years, 51% women) with complete urinary, ocular, and covariable data. METHODS: Urine sodium:creatinine ratio (UNa:Cr; mmol:mmol) was calculated from a midstream urine sample. Ocular parameters were measured as part of a comprehensive eye examination and glaucoma case ascertainment was through a combination of self-report and linked national hospital records. Genetic susceptibility to glaucoma was calculated based on a glaucoma polygenic risk score (PRS) comprising 2 673 common genetic variants. Multivariable linear and logistic regression, adjusted for key sociodemographic, medical, anthropometric, and lifestyle factors, were used to model associations and gene-environment interactions. MAIN OUTCOME MEASURES: Corneal-compensated IOP, optical coherence tomography derived macular retinal nerve fiber layer (mRNFL) and ganglion cell-inner plexiform layer (GCIPL) thickness, and prevalent glaucoma. RESULTS: In maximally adjusted regression models, a one standard deviation increase in UNa:Cr was associated with higher IOP (0.14mmHg; 95% CI, 0.12 to 0.17; P<0.001) and greater prevalence of glaucoma (OR, 1.11; 95% CI, 1.07 to 1.14; P<0.001), but not mRNFL or GCIPL thickness. Compared to those with UNa:Cr in the lowest quintile, those in the highest quintile had significantly higher IOP (0.45mmHg; 95% CI, 0.36 to 0.53, P<0.001) and prevalence of glaucoma (OR, 1.30; 95% CI, 1.17 to 1.45; P<0.001). Stronger associations with glaucoma (P interaction=0.001) were noted in participants with a higher glaucoma PRS. CONCLUSIONS: Urinary sodium excretion, a biomarker of dietary intake, may represent an important modifiable risk factor for glaucoma, especially in individuals at high underlying genetic risk. These findings warrant further investigation as they may have important clinical and public health implications.

Postural effects on blood pressure, intraocular pressure, and ocular perfusion pressure in patients with spinal cord injury.

BACKGROUND: Reduced ocular perfusion pressure (OPP) from hypotension and consistent OPP variability due to blood pressure (BP) fluctuations are predisposing factors for glaucoma. Low resting BP and orthostatic hypotension (OH) in spinal cord injury (SCI) patients may increase the risk of glaucoma post-injury. This study investigated BP, intraocular pressure (IOP), and OPP changes between supine and sitting positions in SCI and normal individuals. METHODS: Twenty SCI cases (high paraplegia, T1-T6 n = 6; low paraplegia, T7-L3 n = 14) and matched controls (1:1) were included. Systolic and diastolic BP (SBP and DBP) were measured digitally, and IOP with rebound tonometry. Measurements were taken one minute apart in both positions. Mean arterial pressure (MAP) was calculated, and OPP was determined using position-specific formulas. RESULTS: No SCI subjects exhibited OH. Both groups experienced significant BP increment (P < 0.05) from supine to sitting. SBP increased by 4.4 ± 8.4 mmHg (SCI) and 3.6 ± 6.2 mmHg (normal), while DBP increased by 4.2 ± 5.1 mmHg (SCI) and 6.7 ± 5.5 mmHg (normal). IOP and OPP decreased significantly (P < 0.05) after postural change in both groups, yet differences between them were not significant. Analysis by injury level revealed lower parameter values in high paraplegia than in low paraplegia, with the latter group showing a more significant reduction in OPP after postural change. CONCLUSION: Postural changes differently affect BP, IOP, and OPP in SCI compared to normal individuals, with variations based on the level of SCI. While not directly assessing glaucoma, the study offers insights into ocular hemodynamics in SCI compared to normals.

Displacement-pressure biparametrically regulated softness sensory system for intraocular pressure monitoring.

High intraocular pressure (IOP) is one of the high-risk pathogenic factors of glaucoma. Existing methods of IOP measurement are based on the direct interaction with the cornea. Commercial ophthalmic tonometers based on snapshot measurements are expensive, bulky, and their operation requires trained personnel. Theranostic contact lenses are easy to use, but they may block vision and cause infection. Here, we report a sensory system for IOP assessment that uses a soft indentor with two asymmetrically deployed iontronic flexible pressure sensors to interact with the eyelid-eyeball in an eye-closed situation. Inspired by human fingertip assessment of softness, the sensory system extracts displacement-pressure information for soft evaluation, achieving high accuracy IOP monitoring (>96%). We further design and custom-make a portable and wearable ophthalmic tonometer based on the sensory system and demonstrate its high efficacy in IOP screening. This sensory system paves a way towards cost-effective, robust, and reliable IOP monitoring.

Pattern of Ocular Injuries Following Road Traffic Accidents Seen at a Tertiary Eye Hospital.

INTRODUCTION: Traffic trauma can lead to ocular damage. Open globe injuries usually have a poor prognosis, which can be ameliorated by prompt diagnosis and appropriate treatment. Nonetheless, few studies have focused on the visual outcomes of patients following traffic accidents. In this study, we aimed to examine the characteristics and prognosis of ocular complications in patients following traffic accidents at a specialized tertiary eye hospital. METHODS: We classified 44 patients from traffic accidents (88 eyes) into groups with equal or better (better group) and worse (worse group) corrected-distance visual acuity than a logarithm of the minimum angle of resolution 0 at the initial presentation. Final corrected-distance visual acuity, intraocular pressure, corneal injury, presence of traumatic cataracts, and treatment were compared between the groups. In addition, a multivariate linear regression analysis was performed to identify factors associated with the final visual acuity. RESULTS: Globe contusion, orbital blowout fracture, traumatic iritis, and trochlear nerve palsy were observed in 14.8%, 3.4%, 2.3%, and 2.3% of the patients, respectively. Topical instillation and ophthalmological treatment/surgery were performed in 17.0% and 9.1% of the patients, respectively. The better group (68 eyes) had significantly better final visual acuity than the worse group (20 eyes) (P < 0.001). However, there was no between-group difference in demographic characteristics. Multivariate analysis demonstrated that there was a significant correlation between the initial and final visual acuities (P < 0.001). CONCLUSIONS: Assessing visual acuity at the initial presentation is crucial for predicting the final visual acuity. Our findings will help to inform ophthalmologists aiming to improve the prognosis and treatment of ocular trauma in patients following traffic accidents.

Effects of Hemodialysis on Intraocular Pressure and Ocular Perfusion Pressure.

INTRODUCTION: Elevated intraocular pressure (IOP) and reduced ocular perfusion pressure (OPP) related to hemodialysis (HD) are risk factors for the development and progression of glaucoma. The aim of this study was to evaluate the effect of HD on IOP and OPP in our patients. METHODS: This was a cross-sectional, descriptive, and analytical study conducted between January 2 and February 5, 2024, in the HD and ophthalmology departments of the Heinrich Lübke Regional Hospital in Diourbel. The IOP of both eyes was measured one hour before the start of the HD session and within 30 minutes after the end of the session, by the same ophthalmologist, for all included patients, using a Goldmann applanation tonometer. OPP were calculated and other socio-demographic data collected. RESULTS: Fifty-eight eyes from 29 chronic HD patients were included. The mean age of the patients was 47.58±12.94 years, with a predominance of women (17 women or 58.6%; sex ratio 0.71). In the left eye, mean IOP increased significantly from 12.21±2.96 mmHg before the HD session to 14.10±4.27 mmHg at the end of the session (p=0.04). For the right eye, the IOP also increased with a strong tendency to significance from 12.97±3.79 mmHg before the HD session to 15.03±5.23 mmHg at the end of the session (p=0.05). OPP did not change significantly after the HD session. CONCLUSION: The HD session significantly increased IOP with no significant change in OPP.

[Factors affecting the hypotensive effect of selective laser trabeculoplasty in primary open-angle glaucoma]. / Faktory, vliyayushchie na gipotenzivnyi effekt selektivnoi lazernoi trabekuloplastiki pri pervichnoi otkrytougol'noi glaukome.

PURPOSE: This study analyzes the influence of various factors on the hypotensive effect of selective laser trabeculoplasty (SLT) in patients with primary open-angle glaucoma (POAG). MATERIAL AND METHODS: A retrospective study of the SLT effect was performed in 582 patients (756 eyes; mean age - 71.9±9.5 years) with POAG stages I-III. The level of intraocular pressure (IOP) decrease was assessed at 1 day, 1, 3, 6, and 12 months after SLT. The relationship between the hypotensive effect and age, gender, glaucoma stage, initial IOP level, number and type of instilled drugs, presence of intraocular lenses, and the surgeon performing the intervention were analyzed. RESULTS: In the entire sample, the hypotensive effect of SLT after 1 day was 4.1±3.4 mm Hg, after 1, 3, 6, and 12 months - 3.7±4.8; 3.5±3.8; 3.1±3.4 and 2.3±3.8 mm Hg, respectively. The hypotensive effect of SLT was most dependent on the preoperative IOP level (R>0.64, p<0.05). No significant correlation was found between the hypotensive effect and the stage of POAG, gender, age, number of hypotensive drugs, phakia/aphakia, and the surgeon. A weaker hypotensive effect of SLT was found in eyes receiving monotherapy with α2-adrenoceptor agonists (p<0.03) and a combination of four drugs (p<0.02). CONCLUSION: SLT is an effective method of additional IOP reduction in POAG at any stage and with any hypotensive regimen. At the same time, the results of its use in real clinical practice indicate the need for more careful IOP control after the procedure, especially in eyes with POAG stage III, as well as in eyes without hypotensive therapy and on the maximum drop regimen.

Effects of alfaxalone, medetomidine, and xylazine on intraocular pressure in domestic pigeons (Columba livia domestica).

OBJECTIVE: To evaluate the effects of alfaxalone, medetomidine, and xylazine on intraocular pressure (IOP) in domestic pigeons (Columba livia domestica). ANIMALS STUDIED: Eight 12-month-old pigeons (16 eyes). PROCEDURES: The pigeons were randomly assigned to three treatment groups (10 mg/kg of alfaxalone, 0.2 mg/kg of medetomidine, or 10 mg/kg of xylazine) with a 7-day washout period. The IOP was measured using a rebound tonometer and calibrated using the formula y = 0.439x + 2.059, where y is the tonometric IOP and x is the actual IOP. RESULTS: All three drugs significantly reduced IOP. Alfaxalone led to the least reduction at 5.2 mm Hg, medetomidine reduced IOP to 12.5 mm Hg, whereas xylazine resulted in the greatest reduction at 15.3 mm Hg. Alfaxalone achieved its maximum IOP reduction in 6 min, whereas medetomidine and xylazine required 95 and 115 min, respectively. Both alpha-2 agonists, medetomidine, and xylazine, showed a prolonged duration of effect and a greater reduction in IOP than those of alfaxalone. All three medications provided adequate sedation without any discernible adverse effects. CONCLUSIONS: The findings revealed the varied effects of these drugs on IOP in pigeons, potentially providing valuable insights that could be useful for broader applications in veterinary medicine.

From pole to pole, life-long research of sleep in extreme environments.

In November 1965, Michel Jouvet accepted me into his laboratory in Lyon as a medical student at a time when sleep research was an adventure. After 4 years of investigations in cats, I obtained my medical doctorate. Being a military physician, I was posted to Antarctica for wintering over and was initiated by Jean Rivolier into the psychology of small isolated human groups. I recorded 180 polysomnographic (PSG) nights in eight of my companions. This was my first contribution to research on human sleep under extreme environments and conditions. I then entered René Hénane's military thermophysiology laboratory, where I analyzed thermal exchanges during human sleep in the heat. Back to the cold, I spent 2 years in Canada and analyzed sleep during the Arctic winter under the direction of Manny W. Radomski, who headed the Defense and Civil Institute of Environmental Medicine and judged my PhD dissertation along with my first two mentors. Throughout my career, I worked in collaboration with Manny Radomski under the auspices of the Franco-Canadian Accord for Defence Research. We studied sleep and exercise, sleep deprivation, and recovery with and without chemical help. He also gave me support during several investigations in Africa. There, I studied normal sleep under various tropical climates (warm and dry in Niger, warm and humid in Côte d'Ivoire and Congo, temperate mid-mountain in Angola). I determined that human African trypanosomiasis, the ravaging sleeping sickness or tsetse disease, is not a hypersomnia, but a disorder of circadian rhythms, notably in the sleep-wake cycle.

Long-term outcomes after acute primary angle closure: case series from Moorfields Eye Hospital, UK.

BACKGROUND: There is limited data regarding the morbidity and progression to primary angle closure glaucoma in those presenting with acute primary angle closure (APAC) in the UK. We aim to report on the vision and intraocular pressure (IOP) outcomes and treatment required after an APAC episode and to identify any risk factors that could predict worse outcomes. METHODS: A retrospective observational case series review including 117 consecutive patients (121 eyes) attending Moorfields Eye Hospital, at a tertiary referral unit in the UK, with APAC was performed. RESULTS: Most patients (73%) had visual acuities of ≥6/12, meeting the UK driving standard, at the final follow-up. Only 15% (17 eyes) had severe visual impairment, as defined by the WHO, in the affected eye, of which 6.6% (eight eyes) were due to glaucoma. The delayed presentation was linked to a higher need for further medical treatment (OR=2.83, 95% CI 1.09 to 7.40, p=0.03). Patients who underwent phacoemulsification were at lower risk of having blindness in the affected eye (OR 0.18, 95% CI 0.05 to 0.69, p=0.01), having elevated IOP (OR 0.10, 95% CI 0.01 to 0.75, p=0.02) or requiring further medical treatment (OR 0.34, 95% CI 0.12 to 0.99, p=0.04). Older age (OR 1.26, 95% CI 1.08 to 1.48, p<0.01) was associated with worse visual outcomes. CONCLUSIONS: APAC causes low long-term visual and treatment morbidity in this largely Caucasian patient group in the UK. Phacoemulsification as a treatment may enhance visual outcomes and reduce the need for further IOP-lowering treatment.

The Effect of Trabecular Aspiration on Intraocular Pressure, Medication and the Need for Further Glaucoma Surgery in Eyes with Pseudoexfoliation Glaucoma.

PURPOSE: To investigate whether trabecular aspiration (TA) has an effective medium-term intraocular pressure (IOP)-lowering and medication-saving effect in patients with pseudoexfoliation glaucoma (PEG). In addition, a subgroup analysis of patients with or without a previous trabeculectomy was performed. METHODS: Records of 290 consecutive eyes with PEG that underwent TA between 2006 and 2012 at the Department of Ophthalmology, Mainz, Germany, were retrospectively analyzed with a follow-up period of 3 years. The main outcomes were IOP and the need for further medical treatment. RESULTS: Of the 290 eyes with PEG that received TA, 167 eyes from 127 patients met the inclusion criteria. Among these eyes, 128 received TA and cataract surgery (Phaco-TA) without having had a trabeculectomy (group I) before, 29 had Phaco-TA after a previous trabeculectomy (group II) and 10 underwent stand-alone TA after a previous trabeculectomy (group III). In the whole cohort, the median IOP decreased immediately after TA and remained significantly lower compared to the baseline throughout the period of 36 months. Likewise, the median number of antiglaucoma drugs was reduced over the whole period. At the same time, in group I, the median IOP and the number of antiglaucoma drugs were reduced over 36 months. In contrast, in the post-trabeculectomy groups (group II and III), the median IOP and the number of antiglaucoma drugs could not be reduced. While most of the patients that received Phaco-TA with or without a previous trabeculectomy (group I and II) did not require further surgical intervention during the follow-up period, almost all patients receiving stand-alone TA after a previous trabeculectomy (group III) needed surgical therapy, most of them between the second and the third year following TA. CONCLUSIONS: Phaco-TA has an effective medium-term pressure-lowering and medication-saving effect, especially in patients without a previous trabeculectomy. In trabeculectomized eyes, the effect of TA is limited but still large enough to delay more invasive surgical interventions in some patients.

High-intensity interval training in patients with glaucoma (HIT-GLAUCOMA): protocol for a multicenter randomized controlled exercise trial.

Background: Glaucoma stands as a prominent global cause of irreversible blindness and the primary treatment approach involves reducing intraocular pressure (IOP). However, around one-third of patients exhibit disease progression despite effective IOP reduction. Microvascular endothelial function, chronic inflammation, and oxidative stress are known to affect retinal neuronal networks and have been associated with disease severity and progression. Exercise training has the potential to counteract these mechanisms as add-on treatment to usual care. Aims: The HIT-GLAUCOMA study will investigate the effects of a 6-month high-intensity interval training (HIIT) on intermediate endpoints such as local retinal microvascular and systemic large artery function, inflammation, and oxidative stress as well as clinical endpoints such as visual field indices, optic nerve rim assessment, retinal nerve fiber layer thickness, IOP, number of eye drops, vision-related quality of life and ocular surface disease symptomatology. Methods: The study is a multi-center randomized controlled clinical trial in patients with both normal tension and high-tension primary open angle glaucoma. Across two study centers, 128 patients will be enrolled and randomized on a 1:1 basis into an exercise intervention group and a usual care control group. The primary microvascular endpoints are retinal arteriolar and venular flicker light-induced dilation at 6 months. The primary endpoint in the systemic circulation is brachial artery flow-mediated dilation at 6 months. Anticipated results: We hypothesize that exercise therapy will improve retinal microvascular function and thus ocular blood flow in patients with glaucoma. As clinical outcomes, we will investigate the effect of exercise on visual field indices, optic nerve rim assessment, retinal nerve fiber layer thickness, IOP, number of eye drops, vision-related quality of life and ocular surface disease symptomatology. Discussion: HIT-GLAUCOMA is a blueprint trial design to study the effect of exercise training on neurodegenerative and cardiovascular diseases. Importantly, patients are also expected to benefit from improvements in general health and cardiovascular co-morbidities. If proven effective, exercise may offer a new add-on treatment strategy to slow glaucoma progression. Clinical Trial Registration Number: The trial is registered at Clinicaltrials.gov under the identifier NCT06058598 and is currently in the recruitment stage.

Long-term Efficacy of Oral Valganciclovir in Presumed Cytomegalovirus Unilateral Hypertensive Anterior Uveitis.

PURPOSE: To describe long-term efficacy and safety of oral valganciclovir in the treatment of presumed cytomegalovirus (CMV) unilateral hypertensive anterior uveitis. METHODS: Retrospective review of 40 patients (40 eyes). RESULTS: All patients presented with high intraocular pressure (mean 39.35 ± 7.58 mmHg), associated with signs of mild anterior uveitis. Oral valganciclovir resulted in control of the intraocular pressures and inflammation in 35 eyes. At the dose of ≥450 mg twice daily, no relapses were documented. The follow-up period ranged from 12 to 108 months (24.45 ± 14.56). At the final follow-up, the intraocular pressure was reduced to 14.92 ± 2.43 mmHg (<0.001). Drug-related complications in the form of leukopenia and azoospermia were reported in one patient. CONCLUSIONS: Oral valganciclovir effectively and safely controls intraocular pressure and inflammation in presumed CMV anterior uveitis. A long-term treatment course seems necessary.

Age-related changes of intraocular pressure in Dutch belted rabbits.

This study investigated intraocular pressure (IOP) in Dutch belted rabbits using two different tonometers, rebound tonometry (TonoVet Plus; TVP) and a Tonopen (Tono-Pen AVIA Vet; TPA). Post-pubescent male Dutch belted rabbits aged 36 weeks (n = 10 animals) were used in the study. IOP measurements were conducted every 2 weeks for 22 weeks using TVP and TPA on both eyes of each rabbit. The average IOP measurements were compared by the paired Student's t-test. Pairwise Pearson's correlation coefficients and Bland-Altman statistics were used. The overall mean IOP measured with TPA was significantly higher than that with TVP (23.5 ± 4.9 vs. 21.8 ± 2.4 mmHg for the right eyes; P = 0.045, and 23.0 ± 4.7 vs. 21.5 ± 2.4 mmHg for the left eyes; P = 0.047). Both tonometers tended to show increased IOP readings with age, and positive correlations between IOP and age were observed with both TPA (r = 0.95, P < 0.001 for right eyes; r = 0.95, P < 0.001 for left eyes) and TVP (r = 0.91, P < 0.001 for right eyes; r = 0.64, P = 0.024 for left eyes). The average bias calculated by subtracting TPA from TVP was - 1.60 (95% confidence intervals - 1.927, - 1.281) mmHg. IOP in post-pubescent Dutch belted rabbits tended to increase with age throughout the 22 week study.

Comparison of intraocular pressure and anterior segment parameters in subjects with asymmetrical primary angle closure disease.

BACKGROUND: To compare intraocular pressure (IOP) and anterior segment parameters between eyes with unilateral primary angle closure glaucoma (PACG) and their fellow eyes with primary angle closure (PAC) or primary angle closure suspect (PACS). METHODS: Subjects underwent anterior segment imaging using 360-degree swept-source optical coherence tomography (SS-OCT, CASIA Tomey, Nagoya, Japan) and ocular investigations including gonioscopy and IOP measurement. Each SS-OCT scan (divided into 8 frames, 22.5 degrees apart) was analysed and an average was obtained for the following anterior segment parameters: iridotrabecular contact (ITC), angle opening distance (AOD750), iris thickness and curvature, anterior chamber width, depth and area (ACW, ACD and ACA) and lens vault (LV). RESULTS: Among 132 unilateral PACG subjects (mean age: 62.91 ± 7.2 years; 59.1% male), eyes with PACG had significantly higher presenting IOP (24.81 ± 0.94 vs. 18.43 ± 0.57 mmHg, p < 0.001), smaller gonioscopic Shaffer grade (2.07 ± 0.07 vs. 2.31 ± 0.07, p < 0.001) and a greater extent of peripheral anterior synechiae (PAS, 1.21 ± 0.21 vs. 0.54 ± 0.16 clock hours, p = 0.001). PACG eyes also exhibited increased ITC, ITC area, greater LV and smaller AOD750, ACD and ACA (all p < 0.05). Using the forward stepwise regression model, an increase in 1 mmHg in presenting IOP before laser peripheral iridotomy (LPI) increases the odds of having PACG by 9% (95% confidence interval 5%-14%). CONCLUSIONS: PACG eyes have higher presenting IOP, smaller anterior segment parameters, greater extent of PAS, and larger LV compared to their fellow eyes with angle closure. Narrower anterior chamber dimensions and higher presenting IOP before LPI may increase risk of chronic elevated IOP and glaucomatous optic neuropathy after LPI.

Long-term efficacy and safety of posterior endoscopic cyclophotocoagulation in refractory glaucoma: A 5-year follow-up study at a tertiary eye center.

PURPOSE: To evaluate the long-term efficacy of endoscopic cyclophotocoagulation (ECP) via a pars plana approach in a large cohort of refractory glaucoma patients DESIGN: Single-center, retrospective, longitudinal, cohort study. METHODS: This study recruited patients who underwent ECP and consecutively visited and were followed up for at least 5 years at Beijing Tongren Eye Center, China from January 2013 to December 2017. All patients underwent a complete ophthalmic examination. Treatment success was defined as 6 mmHg ≤ IOP ≤ 21 mmHg with or without anti-glaucoma medications. RESULTS: A total of 121 eyes of 105 patients including 51 children and 54 adults were enrolled. The mean follow-up was 7.2 ± 1.3 years. The most common glaucoma diagnoses were secondary glaucoma (74 eyes, 61.1 %) and primary congenital glaucoma (19 eyes 15.7 %). The mean extent of the first ECP was 259 degrees. There was an overall decrease in IOP of 38.3 % from 33.3 ± 9.0 mmHg preoperatively to 20.5 ± 7.5 mmHg after surgery, which was statistically significant (P < 0.001). The success rate after 1 or more ECP surgery was 65.3 %. After adjusting for sex, number of prior TCP surgeries and the extent of ECP degree, the failure of ECP was associated with being children (as compared with adults; P = 0.028; OR = 2.549) and higher preoperative IOP (P = 0.001; OR = 1.084). CONCLUSION: ECP is an effective procedure for lowing IOP in refractory glaucoma, particularly in patients who are also candidates for vitreoretinal interventions. Hence, a collaborative approach between glaucoma and retinal specialists is of utmost importance in devising an optimal management strategy for glaucoma treatment.

[Small tidal volume hyperventilation relieves intraocular and intracranial pressure elevation in prone spinal surgery: a randomized controlled trial].

OBJECTIVE: To investigate the effects of different ventilation strategies on intraocular pressure (IOP) and intracranial pressure in patients undergoing spinal surgery in the prone position under general anesthesia. METHODS: Seventy-two patients undergoing prone spinal surgery under general anesthesia between November, 2022 and June, 2023 were equally randomized into two groups to receive routine ventilation (with Vt of 8mL/kg, Fr of 12-15/min, and etCO2 maintained at 35-40 mmHg) or small tidal volume hyperventilation (Vt of 6 mL/kg, Fr of18-20/min, and etCO2 maintained at 30-35 mmHg) during the surgery. IOP of both eyes (measured with a handheld tonometer), optic nerve sheath diameter (ONSD; measured at 3 mm behind the eyeball with bedside real-time ultrasound), circulatory and respiratory parameters of the patients were recorded before anesthesia (T0), immediately after anesthesia induction (T1), immediately after prone positioning (T2), at 2 h during operation (T3), immediately after supine positioning after surgery (T4) and 30 min after the operation (T5). RESULTS: Compared with those at T1, IOP and ONSD in both groups increased significantly at T3 and T4(P < 0.05). IOP was significantly lower in hyperventilation group than in routine ventilation group at T3 and T4(P < 0.05), and ONSD was significantly lower in hyperventilation group at T4(P < 0.05). IOP was positively correlated with the length of operative time (r=0.779, P < 0.001) and inversely with intraoperative etCO2 at T3(r=-0.248, P < 0.001) and T4(r=-0.251, P < 0.001).ONSD was correlated only with operation time (r=0.561, P < 0.05) and not with IOP (r=0.178, P>0.05 at T3; r=0.165, P>0.05 at T4). CONCLUSION: Small tidal volume hyperventilation can relieve the increase of IOP and ONSD during prone spinal surgery under general anesthesia.