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PeerJ 2022The execution of isometric resistance training has demonstrated to cause changes in the ocular physiology. The morphology of the cornea and anterior chamber is of...
OBJECTIVES
The execution of isometric resistance training has demonstrated to cause changes in the ocular physiology. The morphology of the cornea and anterior chamber is of paramount importance in the prevention and management of several ocular diseases, and thus, understating the impact of performing isometric exercise on the eye physiology may allow a better management of these ocular conditions. We aimed to determine the short-term effects of 2-minutes upper-body isometric effort at two different intensities on corneal and anterior eye morphology.
METHODS
Eighteen healthy young adults performed a 2-minutes isometric biceps-curl exercise against two loads relative to their maximum strength capacity (high-intensity and low-intensity) in a randomized manner. An Oculus Pentacam was used to measure the corneal morphology and anterior chamber parameters in both experimental conditions at baseline, during the isometric effort (after 30, 60, 90 and 120 seconds), and after 30 and 120 seconds of passive recovery.
RESULTS
We found that isometric effort causes an increase in pupil size ( < 0.001), and a decrease in the iridocorneal angle ( = 0.005), anterior chamber volume ( < 0.001) and K-flat ( < 0.001) during isometric effort, with these effects being more accentuated in high-intensity condition ( < 0.005 in all cases).Performing 2-minutes upper-body isometric effort did not alter anterior chamber depth, central corneal thickness, corneal volume, and K-steep ( > 0.05 in all cases).
CONCLUSIONS
Our data exhibit that performing 2-minutes of upper-body isometric exercise modifies several parameters of the corneal morphology and anterior eye biometrics, with these changes being greater for the high-intensity exercise condition. The findings of this study may be of relevance for the prevention and management of corneal ectasias and glaucoma.
Topics: Young Adult; Humans; Cornea; Anterior Chamber; Glaucoma; Corneal Diseases
PubMed: 35341047
DOI: 10.7717/peerj.13160 -
Scientific Reports Oct 2023To examine the size of the ciliary body stroma (CBS) in dependence of the morphology of the anterior chamber angle in enucleated human eyes, we histomorphometrically...
To examine the size of the ciliary body stroma (CBS) in dependence of the morphology of the anterior chamber angle in enucleated human eyes, we histomorphometrically examined human enucleated eyes. The study included 107 eyes (with a mean axial length of 25.1 ± 2.8 mm (range 21.0-36.0 mm). The anterior chamber angle was open in 68 eyes and it was closed and endothelialized in 39 eyes. The maximal CBS width (541 ± 210 µm versus 59 ± 179 µm; P < 0.001) and the minimal CBS width (214 ± 107 µm versus 17 ± 55 µm; P < 0.001) and maximal ciliary muscle height (593 ± 557 µm versus 293 ± 111 µm; P = 0.001) were significantly smaller in the angle-closure group than in the open-angle group. Maximal CBS width increased with presence of an open anterior chamber angle (beta: 0.82; B: 517; 95% CI 435, 599; P < 0.001) and longer axial length (beta: 0.17; B: 18.2; 95% CI 4.2, 32.2; P = 0.01). Minimal CBS width increased with the presence of an open anterior chamber angle (beta: 0.48; B: 131; 95% CI 80.4, 181; P < 0.001) and a larger maximal ciliary muscle height (beta: 0.33; B: 0.28; 95% CI 0.12, 0.44; P = 0.001). Maximal ciliary muscle height correlated with the maximal CBS height (beta: 0.35; B: 0.53; 95% CI 0.25, 0.81; P < 0.001). The findings suggest that the CBS size is markedly smaller in eyes with a chronically closed endothelialized anterior chamber angle than in eyes with open angles. The tightening of the angle in eyes with angle-closure may prevent the access of aqueous humor not only to the trabecular meshwork but also to the ciliary body and may reduce the uveoscleral or uveovortex outflow pathway.
Topics: Humans; Ciliary Body; Glaucoma, Angle-Closure; Microscopy, Acoustic; Anterior Chamber; Trabecular Meshwork; Intraocular Pressure
PubMed: 37805618
DOI: 10.1038/s41598-023-44085-8 -
BMC Ophthalmology Jun 2021Micropulse transscleral cyclophotocoagulation (MP-CPC) is a technique that has been approved in recent years to treat glaucoma. MP-CPC causes anterior chamber...
BACKGROUND
Micropulse transscleral cyclophotocoagulation (MP-CPC) is a technique that has been approved in recent years to treat glaucoma. MP-CPC causes anterior chamber inflammation; a relationship with reduced intraocular pressure (IOP) has not been reported. Therefore, we analyzed the correlation between IOP and anterior chamber aqueous flare after MP-CPC.
METHODS
This retrospective study included 37 eyes of 37 patients who underwent MP-CPC between November 2018 and October 2020. IOP and flare values were measured at 1, 4, and 12 weeks after MP-CPC. Correlations were assessed between the percentage IOP reduction and flare elevation by calculating Spearman's rank correlation coefficient.
RESULTS
The percentage IOP reduction at 1 week after surgery was correlated with the flare elevation at 1 week after surgery (ρ = 0.47, P = 0.006). The percentage IOP reduction at 12 weeks after surgery was correlated with the flare elevation at 4 weeks after surgery (ρ = 0.53, P = 0.006).
CONCLUSIONS
A short-term correlation was implied between reduced IOP and flare elevation after MP-CPC.
Topics: Anterior Chamber; Aqueous Humor; Ciliary Body; Humans; Intraocular Pressure; Laser Coagulation; Retrospective Studies; Treatment Outcome; Visual Acuity
PubMed: 34182978
DOI: 10.1186/s12886-021-02012-3 -
Indian Journal of Ophthalmology Dec 2022To report anterior-segment optical coherence tomography (ASOCT) characteristics of different types of corneal and anterior chamber (AC) foreign bodies (FBs) and their...
PURPOSE
To report anterior-segment optical coherence tomography (ASOCT) characteristics of different types of corneal and anterior chamber (AC) foreign bodies (FBs) and their usefulness in diagnosis and management.
METHODS
This is a retrospective descriptive clinical study involving 11 eyes of 11 patients who presented at the outpatient department of a tertiary ophthalmic care center from January 2017 to January 2022. All patients had a diagnosed or suspected corneal FB. All participants underwent a comprehensive ophthalmological examination, followed by slit-lamp photography and ASOCT. FB removal was done where required by an external, internal, or combined approach.
RESULTS
The mean age of patients was 28.2 (7-53) years. Ten were male, and one was female. Seven patients had a definitive positive history of injury; in one, there was a history suggestive of trauma, one had the post-operative complication of scleral buckling surgery, and two patients had a history of insect fall in the eyes. Three patients had acute, four had sub-acute, and four had chronic presentations. Descemet's membrane (DM) breach was suspected in three cases of deep FB, which was later confirmed on ASOCT. In two cases, DM was presumed to be intact clinically, but ASOCT showed an AC penetration. The FB was removed in seven patients, one via slit-lamp, one via an external approach, two via an internal approach, and three via a combined approach.
CONCLUSION
ASOCT facilitates non-invasive rapid imaging of ocular tissue at various depths, provides an accurate assessment of FB characteristics, and thereby serves as an additional tool in our armamentarium for diagnosis and management of deep corneal and AC FBs.
Topics: Humans; Female; Male; Adult; Middle Aged; Tomography, Optical Coherence; Retrospective Studies; Anterior Chamber; Cornea; Foreign Bodies
PubMed: 36453330
DOI: 10.4103/ijo.IJO_878_22 -
Indian Journal of Ophthalmology Sep 2021There is a considerable lack of awareness of slit-lamp measurement of anterior chamber depth (ACD) by the Redmond Smith method (SACD) in present day-to-day clinical... (Observational Study)
Observational Study
Slit-lamp measurement of anterior chamber depth and its agreement with anterior segment optical coherence tomography and Lenstar LS 900 in pseudoexfoliation and normal eyes.
PURPOSE
There is a considerable lack of awareness of slit-lamp measurement of anterior chamber depth (ACD) by the Redmond Smith method (SACD) in present day-to-day clinical practice, which may provide rapid assessment in pseudoexfoliation (PXF) when assessing for angle closure and planning for cataract surgery. This assumes importance not only in outreach clinics but also in the ongoing pandemic caused by the highly contagious novel coronavirus, where social distancing is advocated to contain the spread. We aimed to compare the axial ACD in PXF and normal patients by SACD, and its agreement with the anterior segment optical coherence tomography (ASOCT) and LenstarLS-900.
METHODS
A prospective comparative observational study was done at a tertiary eye care hospital. A PXF group and a normal group of controls were recruited. All eyes were phakic with normal cornea. Any eye with previous intraocular/refractive surgery and cause of other secondary or uncontrolled glaucoma was excluded. SACD was measured clinically via slit-lamp method and also via ASOCT and Lenstar; agreement between the methodologies was plotted.
RESULTS
Fifty patients were recruited in each group. Mean age was 66.82 ± 4.88 years in PXF patients and 65 ± 5.46 years in controls (P = 0.2). ACD was found to be greater in controls compared with the PXF patients; this difference was statistically significant (P < 0.001) across all methodologies. A good agreement with narrow 95% limits of agreement was found between these methodologies.
CONCLUSION
Redmond Smith slit-lamp methodology of estimating the axial ACD is recommended as a rapid, quantifiable, noncontact screening technique during routine examination, especially in primary outreach centers, and is also advantageous during the ongoing pandemic by reducing expendable investigations.
Topics: Aged; Anterior Chamber; COVID-19; Humans; Middle Aged; Prospective Studies; SARS-CoV-2; Tomography, Optical Coherence
PubMed: 34427246
DOI: 10.4103/ijo.IJO_3738_20 -
Medicine Dec 2020The aim of this study was to compare the anterior chamber angle changes after implantation of phakic intraocular lens with and without a central hole for moderate to... (Observational Study)
Observational Study
The aim of this study was to compare the anterior chamber angle changes after implantation of phakic intraocular lens with and without a central hole for moderate to high myopic eyes in Chinese people.This study enrolled 106 eyes of 54 people with intraocular lens V4 implantation and 105 eyes of 53 people with intraocular lens V4c implantation. Postoperative vault, intraocular pressure, and anterior chamber angle changes were assessed using noncontract tonometer and ultrasound biomicroscope, respectively, at 1, 3, 6, and 12months after the surgery.There were no significant differences (all P > .05) between the 2 groups in the depth of the central vault, intraocular pressure, or the width of anterior chamber angle at any time point post-surgery. The anterior chamber angle width in degree had a baseline of 54.40 ± 10.51 in V4c group, and decreased to 27.80 ± 5.62, 26.95 ± 5.56, 27.32 ± 5.66, 27.04 ± 5.47 at 1, 3, 6, and 12 months post-surgery, respectively. Mean preoperative value of 50.62 ± 11.77 decreased to 27.28 ± 6.53, 26.82 ± 6.03, 26.61 ± 5.80, 26.83 ± 5.76 at 1, 3, 6, 12 months, respectively, in V4 group. It had sufficient evidence (P < .001) that anterior chamber angle will narrow done after surgery, but there were no statistically significant differences within groups at any time point after surgery.The anterior chamber angle changes of the V4c group was essentially equivalent to that of conventional V4 group, although implantation of both models will lead to the decrease in anterior chamber angle width.
Topics: Adult; Anterior Chamber; China; Female; Humans; Intraocular Pressure; Lens Implantation, Intraocular; Male; Microscopy, Acoustic; Myopia; Phakic Intraocular Lenses; Retrospective Studies; Tonometry, Ocular; Visual Acuity
PubMed: 33285737
DOI: 10.1097/MD.0000000000023434 -
Indian Journal of Ophthalmology Nov 2022Continuous circular capsulorhexis (CCC) was demonstrated independently by Thomas Neuhann, Kimiya Shimizu, and Howard Gimbel in the 1980s and it finds mention in the...
Continuous circular capsulorhexis (CCC) was demonstrated independently by Thomas Neuhann, Kimiya Shimizu, and Howard Gimbel in the 1980s and it finds mention in the landmark paper by Gimbel and Neuhann. The authors describe a technique of achieving the rhexis in a stable, viscoelastic-filled anterior chamber using the tunnel floor as the entry. This gets covered by the roof of the tunnel postoperatively and, therefore, does not leak. There is no oar-locking or striae even when cystitome goes beyond the edge of the tunnel. As there is no escape of the viscoelastic substance, there is no change in the pressure or shallowing of the anterior chamber. It is a useful technique for beginners. It is of great help in difficult cases like intumescent cataracts, shallow anterior chambers, hyperopes, nanophthalmos, pseudoexfoliation, small non-dilating pupils, intraoperative floppy iris syndrome (IFIS), and phacomorphic glaucoma.
Topics: Humans; Capsulorhexis; Cataract; Anterior Chamber; Glaucoma, Angle-Closure; Miosis
PubMed: 36308155
DOI: 10.4103/ijo.IJO_1459_22 -
Medical Ultrasonography Feb 2021To determine the reliability of transpalpebral ultrasound in B-mode (B-TUS) with a high-resolution linear probe (18 MHz) in estimating both the ocular anterior chamber...
AIMS
To determine the reliability of transpalpebral ultrasound in B-mode (B-TUS) with a high-resolution linear probe (18 MHz) in estimating both the ocular anterior chamber depth (ACD) and axial length (AL), as well as its agreement with the IOL Master 500 optical biometer.
MATERIAL AND METHODS
Cross-sectional study on 82 eyes of 41 volunteers with no history of eye disease. ACD and AL were determined using B-TUS and the IOL Master 500. The agreement between the two tech-niques and the variability of B-TUS (inter- and intra-observer) were analyzed with the Bland-Altman method. To this end, the mean difference between measures±1.96 SD was calculated to determine the limits of agreement (LoA).
RESULTS
The mean difference±1.96SD between B-TUS and the IOL Master 500 was -0.41±0.25mm for ACD (p<0.001) and -0.48±0.45 mm for AL (p<0.001). The maximum variability for B-TUS (average±1.96SD) was 0.00±0.35 mm at the inter-observer level for AL, and 0.00±0.18mm at the intra-observer level for AL.
CONCLUSION
The determination of ACD and AL by B-TUS has a good re-liability and variability, in line with other sonographic techniques. However, it systematically provides smaller measurements than those obtained with the IOL Master 500, similar to the conventional ultrasound techniques. B-TUS could be useful in the assessment and follow-up of a wide range of ophthalmic diseases, in which a high accuracy in ACD and AL is not determinant.
Topics: Anterior Chamber; Biometry; Cross-Sectional Studies; Humans; Reproducibility of Results; Ultrasonography
PubMed: 33621273
DOI: 10.11152/mu-2676 -
Ophthalmology. Glaucoma 2023To investigate the impact of trabecular bypass surgery targeted to angiographically determined high- vs. low-aqueous humor outflow areas on outflow facility (C) and...
PURPOSE
To investigate the impact of trabecular bypass surgery targeted to angiographically determined high- vs. low-aqueous humor outflow areas on outflow facility (C) and intraocular pressure (IOP).
DESIGN
Ex vivo comparative study.
SUBJECTS
Postmortem ex vivo porcine and human eyes.
METHODS
Porcine (n = 14) and human (n = 13) whole globes were acquired. In both species, anterior segments were dissected, mounted onto a perfusion chamber, and perfused using Dulbecco's phosphate buffered solution containing glucose in a constant flow paradigm to achieve a stable baseline. Fluorescein was perfused into the anterior chamber and used to identify baseline segmental high- and low-flow regions of the conventional outflow pathways. The anterior segments were divided into 2 groups, and a 5 mm needle goniotomy was performed in either a high- or low-flow area. Subsequently, C and IOP were quantitatively reassessed and compared between surgery in baseline "high-flow" and "low-flow" region eyes followed by indocyanine green angiography.
MAIN OUTCOME MEASURES
Outflow facility.
RESULTS
In all eyes, high- and low-flow segments could be identified. Performing a 5-mm goniotomy increased outflow facility to a variable extent depending on baseline flow status. In the porcine high-flow group, C increased from 0.31 ± 0.09 to 0.39 ± 0.09 μL/mmHg/min (P = 0.12). In the porcine low-flow group, C increased from 0.29 ± 0.03 to 0.56 ± 0.10 μL/mmHg/min (P < 0.001). In the human high-flow group, C increased from 0.38 ± 0.20 to 0.41 ± 0.20 μL/mmHg/min (P = 0.02). In the human low-flow group, C increased from 0.25 ± 0.11 to 0.32 ± 0.11 μL/mmHg/min (<0.001). There was statistically significant greater increase in C for eyes where surgery was targeted to baseline low-flow regions in both porcine (0.07 ± 0.09 vs. 0.27 ± 0.13, P = 0.007 μL/mmHg/min, high vs low flow) and human eyes (0.03 ± 0.03 vs. 0.07 ± 0.02, P = 0.03 μL/mmHg/min, high vs. low flow).
CONCLUSIONS
Targeting surgery to low-flow areas of the trabecular meshwork yields higher overall facility increase and IOP reduction compared to surgery in high-flow areas.
FINANCIAL DISCLOSURE(S)
Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.
Topics: Humans; Animals; Swine; Aqueous Humor; Trabecular Meshwork; Anterior Chamber; Intraocular Pressure; Trabeculectomy
PubMed: 37348815
DOI: 10.1016/j.ogla.2023.06.008 -
Scientific Reports Nov 2020To evaluate a new method of measuring the intraocular pressure (IOP) in the vitreous cavity. IOPs in the anterior chamber and vitreous cavities of 24 porcine eyes (12...
To evaluate a new method of measuring the intraocular pressure (IOP) in the vitreous cavity. IOPs in the anterior chamber and vitreous cavities of 24 porcine eyes (12 eyes with lenses and 12 eyes without lenses) were measured directly, continuously, and simultaneously. We used a needle as a part of the pressure sensor to measure the anterior chamber IOP and a disk-shaped sensor to measure the vitreous cavity IOP. A significant group-by-condition interaction on the vitreous cavity IOP between the two groups (phakia and aphakia) and four conditions of anterior chamber IOP were observed (F[3,258] = 5.8564, p < 0.001). A positive correlation was observed between the vitreous cavity IOP and anterior chamber IOP in both the phakia group (R = 0.96, p < 0.001) and the aphakia group (R = 0.97, p < 0.001). No significant correlation was observed between the ΔIOPv-a (vitreous cavity IOP - anterior chamber IOP) and anterior chamber IOP in either group (phakia group: R = - 0.18, p = 0.034; aphakia group: R = - 0.029, p = 0.73). The vitreous cavity IOP measured with the new sensor was well-correlated with the anterior chamber IOP in the physiological range tested.
Topics: Animals; Anterior Chamber; Eye; Glaucoma; Intraocular Pressure; Swine; Tonometry, Ocular; Vitreous Body
PubMed: 33239714
DOI: 10.1038/s41598-020-77633-7