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1.
Indian J Ophthalmol ; 70(6): 1920-1930, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35647957

RESUMO

The burden of irreversible vision loss from Glaucoma continues to rise. While the disease pathogenesis is not well understood, intraocular pressure (IOP) is the only modifiable risk factor identified to prevent glaucomatous vision loss. Medical management remains the first-line of treatment in most adult glaucomas and the evolution of medical therapy for glaucoma has followed an exponential curve. This review tracks the rapid development of new medications and drug delivery systems in the recent years. Introduction of Rho kinase inhibitors with an entirely new mechanism of action from that of the currently used anti glaucoma medications has been a significant milestone. Latanoprostene Bunod is a novel, single molecule which provides two active metabolites that work through two different pathways for reducing intra ocular pressure. Bimatoprost implants and travoprost punctum plugs attempt to ease chronic medication use in glaucoma patients. Nanotechnology is an evolving route of drug delivery. Role of cannabinoids in medical management of glaucoma remain equivocal. The relatively short term effect on IOP, the risks of developing tolerance and side effects impacting patients' neurocognitive health greatly outweigh the potential benefit. Research on Latrunculin B, Adenosine receptor agonists, Specific gene silencing and Stem cell therapy are poised to make an impact on glaucoma treatment. While there is some evidence to support the role of Brimonidine in neuroprotection, further research is needed to clarify the role of Memantine and Neurotrophins. Evidence for benefit from dietary supplementation with Alpha lipoic acid, Forskolin , and Ginko Biloba is limited.


Assuntos
Anti-Hipertensivos , Glaucoma , Anti-Hipertensivos/uso terapêutico , Bimatoprost , Glaucoma/tratamento farmacológico , Humanos , Pressão Intraocular , Tonometria Ocular
2.
Oxid Med Cell Longev ; 2022: 3050007, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35651730

RESUMO

Purpose: To observe and compare the efficacy of modified trabeculectomy (TE), Ahmed drainage valve implantation (AGV), and EX-PRESS glaucoma shunt for refractory glaucoma (RG). Methods: The study population of this retrospective study comprised 73 patients (76 eyes) who were suffering from RG and treated with modified TE, AGV, and EX-PRESS glaucoma shunt in our hospital from October 2012 to October 2020. The number of cases who underwent modified TE, AVG, and EX-PRESS glaucoma shunt was 36 (38 eyes). 19 (20 eyes), and 18 patients (18 eyes), respectively. The intraocular pressure (IOP), best-corrected visual acuity (BCVA), postoperative antiglaucoma medications, filter bubble morphology, anterior chamber depth (ACD), successful rate, and postoperative complications were recorded and statistically analyzed preoperative and 1 d, 1 w, 1 mon, 3 mon, 6 mon, and the end follow-up after operation. Results: The BCVA differed insignificantly among the three cohorts before and 6 months after surgery. Compared to preoperative BCVA, the postoperative BCVA of the three groups had no statistical significance. An obvious reduction in IOP was observed in all the three group after operation (P < 0.05). An obvious decrease in antiglaucoma medications was observed after surgery in all the three groups (P < 0.05). The AGV group showed deeper ACD postoperatively, while no marked difference was found in postoperative ACD in the other two groups. The total success rates in modified TE and AGV groups were slightly higher than those in the EX-PRESS group. The three groups differed insignificantly in filter bubble morphology after operation. Conclusion: Modified TE, AGV, and EX-PRESS glaucoma shunt showed equivalent efficacy for RG, which could validly reduce IOP and postoperative antiglaucoma medications. However, the success rates of modified TE and AGV were slightly higher than those of EX-PRESS glaucoma shunt in the last follow-up, and their complications were slightly less than those of the EX-PRESS glaucoma shunt.


Assuntos
Implantes para Drenagem de Glaucoma , Glaucoma , Trabeculectomia , Glaucoma/cirurgia , Humanos , Estudos Retrospectivos , Tonometria Ocular
3.
Invest Ophthalmol Vis Sci ; 63(6): 2, 2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-35648639

RESUMO

Purpose: To characterize the distribution of pigment particles in aqueous drainage structures of DBA/2J mice with different intraocular pressure (IOP) levels. Methods: DBA/2J mice were monitored from 9 to 44 weeks of age. IOP measurements were performed periodically. At 12, 20, 28, and 36 weeks, three mice were randomly selected for each time point and divided into three IOP groups. The morphology, size, and quantity of pigment particles in aqueous drainage structures were determined via transmission electron microscopy combined with ImageJ-based analysis. Between-group differences were evaluated with a one-way analysis of variance and Fisher's least significant difference test. Results: In the anterior chamber, 74.2% (187/252) of pigment particles were round (diameter range, 0.20-0.73 µm), and 25.8% (65/252) were oval (length range, 0.35-1.20 µm ). In the high-IOP group (IOP≥15 mmHg), pigment particles in the trabecular meshwork (TM) were more abundant and larger in size than those in the normal-IOP group (P<0.001). All separate pigment particles in the TM of the high-IOP group were >0.4  µm in size. The diameters of round (IOP≤10 mmHg, 0.44±0.13 µm; IOP between 10 and 15 mmHg, 0.57±0.13 µm; IOP≥15 mmHg, 0.61±0.12 µm) and the lengths of oval (0.65±0.14 µm vs. 0.77±0.12 µm vs. 0.88±0.15 µm, respectively) pigment particles in the TM differed among groups (F=27.258 and F=27.295, respectively; both P<0.001). No such differences were discovered in the iris and around Schlemm's canal (P>0.05). Conclusions: In DBA/2J mice, large and medium pigment particles (>0.4 µm) seem to play an important role in causing aqueous outflow obstruction and IOP elevation.


Assuntos
Glaucoma de Ângulo Aberto , Glaucoma , Animais , Modelos Animais de Doenças , Pressão Intraocular , Camundongos , Camundongos Endogâmicos DBA , Tonometria Ocular , Malha Trabecular
4.
BMC Ophthalmol ; 22(1): 254, 2022 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-35672680

RESUMO

OBJECTIVE: Because of the increase in the number of cases, currently, glaucoma is a significant public health issue that it leads to optic nerve damage and vision loss. High Intraocular Pressure reading indicates that the treatment given to a glaucoma patient is not sufficient/ adequate. Hence, the elevation of intraocular pressure is one of the indicators that, the therapy given to glaucoma patients under treatment is inadequate. Therefore, the main objective of the current study was to investigate predictors for the variation of elevation of IOP readings on glaucoma patients. MATERIALS AND METHODS: A retrospective cohort study design was conducted on 1254 glaucoma patients, whose followed-ups were from September 2015 to August 2016 at Felege Hiwot Teaching and Specialized Hospital, North West Ethiopia. Data analysis was conducted using Statistical Analysis of Systems (SAS) software version 9.2 and AMOS software. The parameter estimation was conducted using the maximum likelihood estimation technique. RESULTS: Main effects like age (ß = 0.01, t-value = 0.15, p-value = 0.018), patients with normal blood pressure (ß = -3.35, t-value = -2.28, p-value = 0.0263), patients without diabetics (ß = -3.79, t-value = -2.47, p-value = 0.014), visiting times (ß = -6.00, t-value = -5.02, p-value = 0.0001), farmer glaucoma patients (ß = -6.04, t-value = 3.87, p-value = 0.0001) had significant and indirect effect for the variation of elevation of IOP on glaucoma patients. Interaction effects like visiting time with existence of diabetes, visiting time with cataract surgery significantly effected on the variable of interest. Hence, both main and interaction effects had significant effects on the variable of interest. This study had identified socio-demographic characteristics, personal/individual behaviors, and clinical factors for the variation of elevation of IOP. The findings, in the current investigation, help health staff to conduct health-related education for awareness creation. Health-related education, about the progression of glaucoma, should be conducted on patients.


Assuntos
Glaucoma , Pressão Intraocular , Glaucoma/diagnóstico , Glaucoma/cirurgia , Humanos , Estudos Retrospectivos , Tonometria Ocular , Transtornos da Visão
5.
Ethiop J Health Sci ; 32(2): 463-466, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35693561

RESUMO

Background: Primary congenital glaucoma is potentially blinding condition characterized by elevated intraocular pressure and optic disc cupping. It is typically bilateral and usually manifest in the first year of life. Spontaneously arrested primary congenital glaucoma can occur, but it is very rare. Case Report: A 32-year-old male patient from North Shewa presented to the department of ophthalmology, Menelik II Hospital with deterioration of vision. On examination he had large corneas with horizontal diameter of 14 mm, increased axial length, faint corneal stromal opacity and Haab's striae of both eyes. Anterior chamber angles were wide open. His intraocular pressure, optic nerve head appearance and visual field in both eyes were normal. He had subluxated dense cataract of the right eye. Conclusion: Late presentation with sequelae of primary congenital glaucoma without optic neuropathy is possible. Regular follow-up of spontaneously arrested congenital glaucoma and scleral fixation of intraocular lens is recommended.


Assuntos
Glaucoma , Tonometria Ocular , Adulto , Câmara Anterior , Etiópia , Glaucoma/diagnóstico , Glaucoma/etiologia , Humanos , Pressão Intraocular , Masculino
7.
Invest Ophthalmol Vis Sci ; 63(5): 25, 2022 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-35604666

RESUMO

Purpose: The lamina cribrosa (LC) is a leading target for initial glaucomatous damage. We investigated the in vivo microstructural deformation within the LC volume in response to acute IOP modulation while maintaining fixed intracranial pressure (ICP). Methods: In vivo optic nerve head (ONH) spectral-domain optical coherence tomography (OCT) scans (Leica, Chicago, IL, USA) were obtained from eight eyes of healthy adult rhesus macaques (7 animals; ages = 7.9-14.4 years) in different IOP settings and fixed ICP (8-12 mm Hg). IOP and ICP were controlled by cannulation of the anterior chamber and the lateral ventricle of the brain, respectively, connected to a gravity-controlled reservoir. ONH images were acquired at baseline IOP, 30 mm Hg (H1-IOP), and 40 to 50 mm Hg (H2-IOP). Scans were registered in 3D, and LC microstructure measurements were obtained from shared regions and depths. Results: Only half of the eyes exhibited LC beam-to-pore ratio (BPR) and microstructure deformations. The maximal BPR change location within the LC volume varied between eyes. BPR deformer eyes had a significantly higher baseline connective tissue volume fraction (CTVF) and lower pore aspect ratio (P = 0.03 and P = 0.04, respectively) compared to BPR non-deformer. In all eyes, the magnitude of BPR changes in the anterior surface was significantly different (either larger or smaller) from the maximal change within the LC (H1-IOP: P = 0.02 and H2-IOP: P = 0.004). Conclusions: The LC deforms unevenly throughout its depth in response to IOP modulation at fixed ICP. Therefore, analysis of merely the anterior LC surface microstructure will not fully capture the microstructure deformations within the LC. BPR deformer eyes have higher CTVF than BPR non-deformer eyes.


Assuntos
Glaucoma , Disco Óptico , Animais , Pressão Intraocular , Macaca mulatta , Tomografia de Coerência Óptica , Tonometria Ocular
8.
PLoS One ; 17(5): e0269261, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35639753

RESUMO

Glaucoma is the leading cause of irreversible blindness worldwide. Therapies for glaucoma are directed toward reducing intraocular pressure (IOP), the leading risk factor and only reliable therapeutic target via topical medications or with procedural intervention including laser or surgery. Though topical therapeutics are typically first line, less than 50% of patients take drops as prescribed. Sustained release technologies that decrease IOP for extended periods of time are being examined for clinical use. We recently identified Stanniocalcin-1, a naturally occurring hormone, as an IOP-lowering agent. Here, we show that a single injection into the anterior chamber of mice with an adeno-associated viral vector containing the transgene of stanniocalcin-1 results in diffuse and sustained expression of the protein and produces IOP reduction for up to 6 months. As the treatment effect begins to wane, IOP-lowering can be rescued with a repeat injection. Aqueous humor dynamic studies revealed an increase in outflow facility as the mechanism of action. This first-in-class therapeutic approach has the potential to improve care and reduce the rates of vision loss in the 80 million people worldwide currently affected by glaucoma.


Assuntos
Glaucoma , Hipotensão Ocular , Animais , Glaucoma/tratamento farmacológico , Glaucoma/genética , Glicoproteínas , Humanos , Pressão Intraocular , Camundongos , Tonometria Ocular , Transgenes
9.
Transl Vis Sci Technol ; 11(5): 21, 2022 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-35583885

RESUMO

Purpose: To accurately evaluate pressure changes during vitrectomy in a rigid model of the vitreous chamber and to test the efficiency of the EVA phacovitrectomy system (Dutch Ophthalmic Research Center) in terms of compensation of intraocular pressure variations. Methods: We tested 23-, 25-, and 27-gauge double-blade vitreous cutters in both vented global pressure control and automatic infusion compensation (AIC) modes in a vitreous chamber model, mimicking the real surgical procedure. Balanced salt solution and artificial vitreous, similar to the real vitreous body, were used. We tested both standard-flow (SF) and high-flow (HF) infusion systems, varying the infusion pressure between 20 and 40 mm Hg. In each experiment, flow rate was also measured. Results: Pressure drop was rapidly and efficiently compensated when 23- and 25-gauge cutters were used in AIC mode, with infusion pressures ranging between 30 and 55 mm Hg. The 27-gauge cutter was less efficient in compensating pressure variations. Pressure fluctuations related to the high-frequency motion of the cutter blade were small compared to the overall pressure variations. The use of the HF infusion system resulted in larger flow rates and lower pressure changes compared to the SF infusion system. Conclusions: Despite the rigid material of the model, the present pressure measurements are in line with previous studies performed on porcine eye. The use of AIC mode compensates intraoperative pressure drops efficiently, with both 23- and 25-gauge cutters. The HF infusion system is more efficient than the SF infusion system. Translational Relevance: The AIC infusion mode efficiently compensates intraoperative pressure drops, in both 23- and 25-gauge experimental vitrectomy. The HF infusion system resulted in larger flow rate and lower pressure changes.


Assuntos
Oftalmopatias , Vitrectomia , Animais , Oftalmopatias/cirurgia , Microcirurgia/métodos , Suínos , Tonometria Ocular , Vitrectomia/métodos , Corpo Vítreo/cirurgia
10.
Exp Eye Res ; 220: 109103, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35525299

RESUMO

The key risk factor for glaucoma is elevation of intraocular pressure (IOP) and alleviating it is the only effective therapeutic approach to inhibit further vision loss. IOP is regulated by the flow of aqueous humour across resistive tissues, and a reduction in outflow facility, is responsible for the IOP elevation in glaucoma. Measurement of outflow facility is therefore important when investigating the pathophysiology of glaucoma and testing candidate treatments for lowering IOP. Due to similar anatomy and response to pharmacological treatments, mouse eyes are a common model of human aqueous humour dynamics. The ex vivo preparation, in which an enucleated mouse eye is mounted in a temperature controlled bath and cannulated, has been well characterised and is widely used. The postmortem in situ model, in which the eyes are perfused within the cadaver, has received relatively little attention. In this study, we investigate the postmortem in situ model using the iPerfusion system, with a particular focus on i) the presence or absence of pressure-independent flow, ii) the effect of evaporation on measured flow rates and iii) the magnitude and pressure dependence of outflow facility and how these properties are affected by postmortem changes. Measurements immediately after cannulation and following multi-pressure facility measurement demonstrated negligible pressure-independent flow in postmortem eyes, in contrast to assumptions made in previous studies. Using a humidity chamber, we investigated whether the humidity of the surrounding air would influence measured flow rates. We found that at room levels of humidity, evaporation of saline droplets on the eye resulted in artefactual flow rates with a magnitude comparable to outflow, which were eliminated by a high relative humidity (>85%) environment. Average postmortem outflow facility was ∼4 nl/min/mmHg, similar to values observed ex vivo, irrespective of whether a postmortem delay was introduced prior to cannulation. The intra-animal variability of measured outflow facility values was also reduced relative to previous ex vivo data. The pressure-dependence of outflow facility was reduced in the postmortem relative to ex vivo model, and practically eliminated when eyes were cannulated >40 min after euthanisation. Overall, our results indicate that the moderately increased technical complexity associated with postmortem perfusion provides reduced variability and reduced pressure-dependence in outflow facility, when experimental conditions are properly controlled.


Assuntos
Humor Aquoso , Glaucoma , Animais , Humor Aquoso/fisiologia , Pressão Intraocular , Camundongos , Perfusão/métodos , Tonometria Ocular , Malha Trabecular
11.
J Nepal Health Res Counc ; 19(4): 824-829, 2022 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-35615845

RESUMO

BACKGROUND: Elevated intraocular pressure in thyroid associated orbitopathy may lead to development of secondary glaucoma in them. This study evaluated IOP in primary gaze correlation with clinical activity score in them. METHODS: A cross-sectional study was conducted from November 2020 to October 2021.Information on age, gender, thyroid function test, intraocular pressure, cup-disc ratio and clinical activity score were recorded. Purposive sampling was done. Statistical analysis was done using Statistical Package for Social Sciences version 21. RESULTS: Total of 74 thyroid dysfunction patients was included in the study. There were14.86% patients with raised intraocular pressure. The mean intraocular pressure in hyperthyroidism was 15.4 ± 1.92 mm Hg and 15.48 ± 2.11mm Hg on right and left eyes respectively and in hypothyroidism, it was 15.08 ± 2.7mmHg and 15.12 ± 3.02 mmHg on right and left eyes respectively. The mean clinical activity score was 1.06 ± 1.23 mmHg. The mean intraocular pressure in eyes in active stage (n=9) was 16.3 ± 3.4 mm Hg, which was not significantly different from the mean intraocular pressure of 15 ± 2.4 mm Hg in inactive eyes (64), p= 0.1. Clinical activity score showed a significant correlation (p=0.03) with intraocular pressure in right eyes whereas it showed no significant correlation with intraocular pressure in left eyes (p=0.37). CONCLUSIONS: In this study elevated intraocular pressure occurred in about 1 in 7 thyroid associated orbitopathy. It also had positive correlation with clinically activity score in right eyes. Regular intraocular pressure measurement should be done in thyroid associated orbitopathy to prevent intraocular morbidity.


Assuntos
Oftalmopatia de Graves , Pressão Intraocular , Estudos Transversais , Humanos , Nepal/epidemiologia , Tonometria Ocular
12.
J Ocul Pharmacol Ther ; 38(5): 354-358, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35613407

RESUMO

Purpose: To retrospectively evaluate the 1-year efficacy and safety of single-agent of omidenepag isopropyl in patients with normal-tension glaucoma (NTG). Methods: One hundred patients (100 eyes) newly administered omidenepag isopropyl were enrolled. Intraocular pressure (IOP) was compared at baseline and 3, 6, 9, and 12 months after administration. The mean deviation values at baseline and 12 months measured using the Humphrey visual field test (30-2 Swedish Interactive Threshold Algorithm standard) were compared. Adverse reactions and dropouts were observed. Results: IOP significantly decreased from 15.5 ± 2.7 mmHg at baseline to 13.3 ± 2.5 mmHg after 3 months, 13.7 ± 2.3 mmHg after 6 months, 13.9 ± 2.4 mmHg after 9 months, and 13.7 ± 2.3 mmHg after 12 months (P < 0.0001). There was no significant difference in the mean deviation values at baseline (-3.66 ± 3.49 dB) and after 12 months (-3.41 ± 3.80 dB). Adverse reactions occurred in 9 patients (9.0%): conjunctival hyperemia (n = 6), eye pain (n = 1), iritis (n = 1), and blepharitis (n = 1). Twenty-one patients (21.0%) discontinued administration because of changes in medication (n = 7), interruption of visits (n = 5), adverse reactions (n = 4), and others. Conclusions: After administering omidenepag isopropyl, the IOP in patients with NTG decreased within 1 year, visual fields were maintained, and safety was satisfactory. Omidenepag isopropyl can be used as the first-line medication for patients with NTG.


Assuntos
Glaucoma de Baixa Tensão , Glicina/análogos & derivados , Humanos , Pressão Intraocular , Glaucoma de Baixa Tensão/tratamento farmacológico , Pirazóis , Piridinas , Estudos Retrospectivos , Tonometria Ocular
13.
Rom J Ophthalmol ; 66(1): 75-78, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35531446

RESUMO

A 36-year-old female patient presented to our clinic with a two months history of diplopia and dizziness. The symptoms appeared gradually and increased in frequency and intensity. She had no significant medical history and she did not take any medication. A full ophthalmological consult was performed, which revealed restricted ocular motility in the left eye (LE), in left gaze. Otherwise, the examination showed no pathological findings: best corrected visual acuity (BCVA) both eyes (OU) 1 (Snellen chart), normal slit lamp examination and pupillary reflexes, normal intraocular pressure (IOP) and fundus aspect. Diplopia tests revealed a horizontal diplopia, exacerbated in left gaze. Sixth nerve palsy suspicion was raised and the patient was directed to the neurology department. Following magnetic resonance imaging, with angiographic sequence, a complex intracerebral vascular malformation that interacted with the cranial nerves and determined horizontal diplopia, was found. For a correct diagnosis, we needed a good collaboration between various medical specialties, especially ophthalmology and neurology, because patients with diplopia often present for the first time at the ophthalmologist. Abbreviations: BCVA = best corrected visual acuity, IOP = intraocular pressure, LE = left eye, RE = right eye.


Assuntos
Doenças do Nervo Abducente , Diplopia , Doenças do Nervo Abducente/complicações , Adulto , Diplopia/diagnóstico , Diplopia/etiologia , Feminino , Humanos , Pressão Intraocular , Tonometria Ocular , Acuidade Visual
14.
J Mech Behav Biomed Mater ; 131: 105252, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35526347

RESUMO

Keratoconus is an eye condition caused by localized thinning of the corneal tissue, which leads to a characteristic cone-shaped protrusion of the cornea. We investigate the mechanical behavior of keratoconus and suspect keratoconus corneas versus healthy corneas by using patient-specific finite element models. Patient-specific geometries of the corneas are obtained from diagnostic images provided by corneal topographer, transformed into solid models, and discretized in hexahedral elements. For the diseased corneas, a suitable reduction of the stiffness is applied within a limited region of the cornea around the conus. After the identification of the stress-free configuration, the models are used to simulate pressurization tests up to 40 mmHg. The material parameters have been estimated within the stress-free configuration identification procedure. As expected, numerical results reveal a more compliant behavior for the diseased corneas in terms of apex displacement plots as a function of the intraocular pressure, with diseased corneas experiencing up to 44% increase in apex displacement compared to healthy corneas. The maps of the stress confirm, for the diseased corneas, a marked increase of the maximum tensile stress, on both anterior and posterior surfaces, to be ascribed mainly to the reduction of the corneal thickness. Stress maps also show, for keratoconus corneas, a marked increase of the ratio between posterior and anterior tensile stress in the conus. Numerical analyses are used to construct the refractive power maps, revealing clearly that the maximum dioptric power in keratoconus corneas is at the center of the cone-shape rather than at the apex.


Assuntos
Ceratocone , Córnea , Humanos , Pressão Intraocular , Tonometria Ocular
15.
Sci Rep ; 12(1): 8354, 2022 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-35589817

RESUMO

Corneal mechanical changes are believed to occur before any visible structural alterations observed during routine clinical evaluation. This study proposed developing an elastography technique based on torsional waves (TWE) adapted to the specificities of the cornea. By measuring the displacements in the propagation plane perpendicular to the axis of the emitter, the effect of guided waves in plate-like media was proven negligible. Ex vivo experiments were carried out on porcine corneal samples considering a group of control and one group of alkali burn treatment ([Formula: see text]OH) that modified the mechanical properties. Phase speed was recovered as a function of intraocular pressure (IOP), and a Kelvin-Voigt rheological model was fitted to the dispersion curves to estimate viscoelastic parameters. A comparison with uniaxial tensile testing with thin-walled assumptions was also performed. Both shear elasticity and viscosity correlated positively with IOP, being the elasticity lower and the viscosity higher for the treated group. The viscoelastic parameters ranged from 21.33 to 63.17 kPa, and from 2.82 to 5.30 Pa s, for shear elasticity and viscosity, respectively. As far as the authors know, no other investigations have studied this mechanical plane under low strain ratios, typical of dynamic elastography in corneal tissue. TWE reflected mechanical properties changes after treatment, showing a high potential for clinical diagnosis due to its rapid performance time and paving the way for future in vivo studies.


Assuntos
Técnicas de Imagem por Elasticidade , Animais , Córnea/diagnóstico por imagem , Elasticidade , Técnicas de Imagem por Elasticidade/métodos , Suínos , Tonometria Ocular , Viscosidade
16.
Transl Vis Sci Technol ; 11(4): 24, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-35486039

RESUMO

Purpose: To improve outcomes for subretinal implantation surgery in pigs. Methods: Analysis of variables affecting the success of subretinal implantation surgery was performed on videos of 37 surgeries. Ex vivo experiments were conducted to measure intraocular pressure (IOP) and test various prototyped implanters for effectiveness at maintaining IOP. Results: A video analysis revealed a prolonged sclerotomy open time owing to a combination of uncontrolled bleeding and excessive fluid outflow often resulting in retinal prolapse. Precauterization of the choroid before full-thickness sclerotomy (n = 10) resulted in a reduced incidence of uncontrolled bleeding from 39.1% (9/23) versus 0% (0/10) (P = 0.005) and improved implantation success from 73% to 90%. An ex vivo analysis of the IOP revealed a mean decrease in the IOP from 30.2 ± 3.0 mm Hg to 5.0 ± 2.1 mm Hg after a fully penetrating sclerotomy. To address this situation, we produced a series of plugs that integrated with a custom implant insertion device to seal the sclerotomy during implantation. The use of the plugs was cumbersome, however, and so we opted instead to increase the width of the inserter tip to fill the open sclerotomy. This improved device restored and maintained IOP during implantation (27.1 ± 1.9 mm Hg). Combined with precauterization the improved inserter resulted in 100% successful implantation (n = 4). Conclusions: For subretinal implantation in pigs, a modified procedure to precauterize the choroid before sclerotomy combined with an instrument that better fills the scleral opening decreases bleeding, hypotony, and open sclerotomy time, improving the success rate. Translational Relevance: Better management of IOP and bleeding from a sclerotomy will improve implant-based therapies.


Assuntos
Implantes para Drenagem de Glaucoma , Glaucoma de Ângulo Aberto , Animais , Glaucoma de Ângulo Aberto/cirurgia , Pressão Intraocular , Suínos , Tonometria Ocular , Resultado do Tratamento
17.
Sci Rep ; 12(1): 6959, 2022 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-35484198

RESUMO

Femtosecond laser-assisted keratoplasty has been proposed as a treatment option for corneal transplantation. In this study, we investigated and compared the outcomes of Ziemer Z8 femtosecond laser (FSL)-assisted penetrating keratoplasty (PK) using a liquid interface versus flat interface. Thirty fresh porcine eyes underwent FSL-assisted PK with the Z8 using different levels of energies (30%, 90% or 150%) and different interfaces (liquid or flat). The real-time intraocular pressure (IOP) changes, incision geometry, corneal endothelial damage, as well as the accuracy of laser cutting and tissue reaction, were performed and compared. We found that the overall average IOP at all laser trephination stages was significantly higher with the flat interface, regardless of the energy used (68.9 ± 15.0 mmHg versus 46.1 ± 16.6 mmHg; P < 0.001). The overall mean laser-cut angle was 86.2º ± 6.5º and 88.2º ± 1.0º, for the liquid and flat platform respectively, indicating minimal deviation from the programmed angle of 90º. When high energy (150%) was used, the endothelial denuded area was significantly greater with the flat interface than with liquid interface (386.1 ± 53.6 mm2 versus 139.0 ± 10.4 mm2 P = 0.02). The FSL cutting did not cause obvious tissue reaction alongside the laser cut on histological evaluation. The results indicated a liquid interface is the preferable choice in FSL-assisted corneal transplantation.


Assuntos
Lesões da Córnea , Transplante de Córnea , Terapia a Laser , Animais , Transplante de Córnea/métodos , Ceratoplastia Penetrante/métodos , Terapia a Laser/métodos , Lasers , Suínos , Tonometria Ocular
18.
Turk J Ophthalmol ; 52(2): 91-95, 2022 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-35481729

RESUMO

Objectives: To analyze emergency and outpatient admissions by glaucoma patients during complete lockdown due to coronavirus disease 2019 (COVID-19) to assess the effect of pandemic-related complete lockdown on glaucoma patients. Materials and Methods: This retrospective chart review included all glaucoma patients who were either examined and/or underwent emergency surgery between March 11, 2020 and May 31, 2020, a period of complete COVID-19-related lockdown in Turkey. The data were compared with data from patients seen during the same time period in 2019. Visual acuity and intraocular pressure data from patients examined after the lifting of the lockdown were also evaluated. Results: According to Turkish Ministry of Health guidelines, only emergency examinations and surgeries could be performed during the 82 days of the COVID-19 lockdown. During this period, a total of 11 eyes of 10 patients were operated and 123 patients were examined in the outpatient clinic. During the same period in 2019, 122 surgeries were performed, 39 of which were emergencies. In the first 4 weeks after the lockdown ended, 163 patients were examined at the outpatient clinic and marked visual loss was detected in 10 eyes of 9 (5.5%) patients who did not attend follow-up visits due to the pandemic. Conclusion: During the lockdown, emergency surgeries related to glaucoma decreased by 71.7% and marked visual loss was detected in 5.5% of the patients examined after the lockdown. These findings suggest that some patients were unable to present to clinics despite needing emergency care.


Assuntos
COVID-19 , Glaucoma , COVID-19/epidemiologia , Controle de Doenças Transmissíveis , Glaucoma/complicações , Glaucoma/epidemiologia , Glaucoma/cirurgia , Humanos , Estudos Retrospectivos , Tonometria Ocular
19.
J Glaucoma ; 31(6): 406-412, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35394466

RESUMO

PRCIS: All devices evaluated in this study showed a significant underestimation in intraocular pressure (IOP) measurement after myopic photorefractive keratectomy (PRK), Goldmann tonometer more than others. Corneal biomechanics indicated a different influence on the different kinds of tonometry. PURPOSE: The aim was to investigate the reliability of Goldmann applanation tonometry (GAT), rebound tonometry (RT), ocular response analyzer (ORA), Corvis ST (CST), and dynamic contour tonometry (DCT) in IOP evaluation after myopic PRK. MATERIALS AND METHODS: One eye of 145 patients who underwent myopic PRK for a refractive defect ranging from -10.25 to -0.50 D (mean -4.69±2.00 D) was included in this retrospective comparative study. A complete eye visit with corneal tomography and IOP measurement with GAT, DCT, ORA, RT, and CST was performed before surgery and at 1, 3, and 6 months follow-up. Values provided by each device were tested and compared at each follow-up. Correlation analyses were run between changes in IOP and the corneal, morphologic and biomechanical parameters were measured after PRK. RESULTS: GAT, DCT, ORA, RT, and CST showed a significant (P<0.01) underestimation of IOP at 6 months follow-up. GAT showed the greatest underestimation (-14.1%) and stronger correlations with corneal deformation parameter changes, whereas ORA, DCT, and RT appeared to be less conditioned by these variations. At 6 months follow-up DCT, ORA, RT, and CST provided IOP values with nonsignificant differences compared with GAT before PRK. CONCLUSIONS: Each tested tonometer showed a significant IOP underestimation after myopic PRK. As this was most observed with GAT compared with all devices, we suggest DCT, ORA, RT, or CST to evaluate IOP in these patients following surgery.


Assuntos
Miopia , Ceratectomia Fotorrefrativa , Córnea/anatomia & histologia , Humanos , Pressão Intraocular , Miopia/cirurgia , Reprodutibilidade dos Testes , Estudos Retrospectivos , Tonometria Ocular
20.
Klin Monbl Augenheilkd ; 239(4): 429-434, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35472784

RESUMO

PURPOSE: Several new implant devices have recently been introduced to glaucoma surgery using various techniques for reducing intraocular pressure (IOP). Two implants introduced during the past couple of years, XEN45 and PreserFlo Microshunt, are both designed to control subconjunctival filtration. There are two Swiss multicenter studies that collected the data retrospectively to analyze the efficacy and safety of these two devices separately. In this study, we report the analysis of the combined data subset from the University Hospital of Basel. SUBJECTS AND METHODS: The XEN45 implantation technique was introduced to Basel University Hospital in 2016 and PreserFlo Microshunt in 2018. Sixty operated patients, thirty in each group, were operated on by one surgeon, clinically followed up, and their data retrospectively analyzed from medical records. Only standalone procedures, without combined phacoemulsification, were considered in this analysis; the lens status, however, was neither an inclusion nor an exclusion criterion. Further inclusion criteria were the diagnosis of open-angle glaucoma, no previous glaucoma surgery, other than laser trabeculoplasty, and complete medical records during the 12 months of follow-up. IOP reduction during a 12-month postoperative period was the primary outcome measure as well as the number of IOP reducing drugs. The number of subsequent surgical interventions and complications/adverse events are descriptively reported. RESULTS: Patient age, gender, ophthalmological diagnosis, and initial preoperative IOP were well balanced between the two groups. Postoperative IOP course was comparable between the two methods for the first 12 months. IOP measurements were taken preoperatively and then on the first postop day, week 1, month 1, and months 3, 6, and 12 for the PreserFlo Microshunt vs. XEN45 (mmHg): 23.6 vs. 24.9, 9.0 vs. 8.9, 11.4 vs. 10.6, 13.0 vs.18.3, 16.8 vs.15.1, 15.9 vs.15.0, and 15.4 vs.14.5, respectively. IOP reducing medications were also comparable between the two groups. The study showed that subsequent interventions were more frequent in the XEN45 (13) than in the PreserFlo Microshunt group (7). CONCLUSION: Both methods demonstrate satisfactory IOP control within a 12-month postoperative period with practically no serious adverse events/complications, but with relatively high numbers of subsequent interventions (needlings), particularly in the XEN45 group.


Assuntos
Implantes para Drenagem de Glaucoma , Glaucoma de Ângulo Aberto , Glaucoma , Glaucoma/complicações , Implantes para Drenagem de Glaucoma/efeitos adversos , Glaucoma de Ângulo Aberto/complicações , Humanos , Estudos Retrospectivos , Tonometria Ocular
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