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1.
Exp Eye Res ; 171: 164-173, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29526795

RESUMEN

Cultured trabecular meshwork (TM) cells are a valuable model system to study the cellular mechanisms involved in the regulation of conventional outflow resistance and thus intraocular pressure; and their dysfunction resulting in ocular hypertension. In this review, we describe the standard procedures used for the isolation of TM cells from several animal species including humans, and the methods used to validate their identity. Having a set of standard practices for TM cells will increase the scientific rigor when used as a model, and enable other researchers to replicate and build upon previous findings.


Asunto(s)
Técnicas de Cultivo de Célula , Separación Celular/métodos , Guías como Asunto , Malla Trabecular/citología , Factores de Edad , Animales , Biomarcadores/metabolismo , Consenso , Feto , Humanos , Donantes de Tejidos , Conservación de Tejido , Recolección de Tejidos y Órganos , Malla Trabecular/metabolismo
2.
Bioengineering (Basel) ; 11(5)2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38790278

RESUMEN

This study investigated the effect of intraocular pressure (IOP) reduction on pulsatile displacement within the optic nerve head (ONH) in primary open-angle glaucoma (POAG) patients with and without axial myopia. Forty-one POAG patients (19 without myopia, 9 with axial myopia and 13 glaucoma with no intervention) participated. Swept-source optical coherence tomography (OCT) videos of the ONH were obtained before and after IOP-lowering treatment (medical or surgical) achieving a minimum IOP drop of 3 mmHg. A demons registration-based algorithm measured local pulsatile displacement maps within the ONH. Results demonstrated a significant 14% decrease in pulsatile tissue displacement in the non-myopic glaucoma cohort after intervention (p = 0.03). However, glaucoma patients with axial myopia exhibited no statistically significant change. There were no significant changes in the pulsatile ONH deformation in the control group. These findings suggest a potential link between IOP reduction and reduced pulsatile displacement within the ONH in POAG patients without myopia, offering new insights into the disease's pathophysiology and warranting further investigation into underlying mechanisms and clinical implications.

3.
Am J Ophthalmol Case Rep ; 32: 101940, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37860670

RESUMEN

Purpose: To evaluate ocular rigidity and choroidal thickness changes in response to microgravity and the Valsalva maneuver in a private astronaut. Methods: Ophthalmological examination and Optical Coherence Tomography were performed before, during, and after space flight. Choroidal thickness was measured at all time points at rest and during the Valsalva maneuver. Ocular rigidity was obtained before and after flight using a non-invasive method enhanced with deep learning-based choroid segmentation. Results: Ocular rigidity decreased after space flight compared to baseline. There was an increase in average choroidal thickness during the Valsalva maneuver compared to the resting condition before, during, and after space flight, and such increase was greater when the Valsalva maneuver was performed during space flight. Conclusions and importance: The data indicates biomechanical changes to ocular tissues because of space flight and greater choroidal thickness increase. The findings could lead to a better understanding of space flight-associated neuro-ocular syndrome and may have repercussions for short duration missions in a nascent industry.

4.
J Glaucoma ; 28(3): 223-230, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30624387

RESUMEN

OBJECTIVE: To compare the central corneal thickness (CCT) between different ethnicities and particularly Asian subethnic groups that may contribute to the different glaucoma diagnoses using the optical low-coherence reflectometry technique. METHODS: A retrospective study of 6 years including 1512 eyes of 929 patients of the Beckman vision center, University of California, San Francisco from 2011 to 2017 had their biometric parameters, including CCT, measured with the Lenstar. Patients were categorized into African Americans, Caucasians, Hispanics, Pacific Islanders, and Asians. Asians were further subcategorized into Chinese, Vietnamese, Koreans, Filipinos, and Japanese. RESULTS: Among 1356 patients who had their CCT measured by Lenstar from 2011 to 2017, 1512 eyes of 929 patients were included. The study population included 462 Caucasians (52.96%), 60 African Americans (6.46%), 92 Hispanics (9.9%), 32 Pacific Islanders (3.44%), 130 Chinese (13.99%), 52 Filipinos (5.6%), 37 Vietnamese (3.98%), 34 Koreans (3.66%), and 30 Japanese (3.23%). African Americans had the thinnest CCT with a mean of 518.62±40.3 followed by Asians with a mean of 539.29±34.1. Among the Asian study sample, the Chinese had the thinnest CCT with a mean of 537.66±32.5. CCT was adjusted for age, sex, glaucoma diagnosis, diabetes status, and prostaglandin analogs use for >12 months. CONCLUSIONS: Optical low-coherence reflectometry is a widely used technology, which can measure CCT. Our study confirms that African Americans have the thinnest corneas followed by Asians. In the latter group, relatively thin CCT may partly explain their high rates of normal-tension glaucoma.


Asunto(s)
Pueblo Asiatico/etnología , Córnea/anatomía & histología , Glaucoma/etnología , Adulto , Negro o Afroamericano , Anciano , Biometría , Femenino , Glaucoma/fisiopatología , Humanos , Interferometría/métodos , Presión Intraocular/fisiología , Luz , Masculino , Persona de Mediana Edad , Tamaño de los Órganos , Estudios Retrospectivos , Población Blanca
5.
Prog Retin Eye Res ; 64: 77-83, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29374584

RESUMEN

Cataract extraction is a safe and effective surgery that has a lowering effect on the intraocular pressure. The specific mechanisms for this effect are still unclear. A direct inflammatory effect on the trabecular meshwork, alteration of the blood aqueous barrier, changes in the ciliary body and mechanical changes of the anterior segment anatomy are the key to understand cataract surgery and it's effects on aqueous humor dynamics. Additionally, with the advent of AS OCT, changes in the anterior segment of the eye have been studied and several parameters (such as lens vault, angle opening distance and anterior chamber depth) have been identified as predictors of intraocular pressure change. In eyes with narrow angles there is a greater drop in intraocular pressure after cataract surgery and it is correlated with parameters related to anterior chamber space. It is safe to affirm that cataract surgery is an important part of the modern glaucoma treatment and evidence should be analyzed as part of a bigger picture in order to more accurately understand its clinical relevance.


Asunto(s)
Segmento Anterior del Ojo/anatomía & histología , Catarata , Presión Intraocular/fisiología , Hipertensión Ocular/cirugía , Facoemulsificación , Catarata/fisiopatología , Glaucoma/fisiopatología , Glaucoma/cirugía , Humanos , Hipertensión Ocular/fisiopatología
6.
Dev Ophthalmol ; 59: 179-190, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28442697

RESUMEN

PURPOSE: Cyclodestructive procedures are traditionally used in cases of glaucoma that are refractory to medical and surgical therapy. The goal of this chapter is to describe the indications, contraindications, techniques, and pitfalls of cyclodestructive procedures, including transscleral cyclophotocoagulation (TCP), micropulse TCP (MP-TCP), endoscopic cyclophotocoagulation (ECP), and ultrasound cilioplasty. METHODS: A literature search for cyclodestructive techniques was performed, and relevant studies were included for evaluation and review. RESULTS: It is encouraging that TCP seems relatively efficacious even for patients who have been refractory to other treatments, depending on the energy setting, follow-up period, and definition of success. Repeated TCP is often required. TCP was more often used in eyes with limited visual potential caused by severe forms of glaucoma than in eyes with good visual potential. Serious complications were significant vision loss, inflammation, hypotony, and phthisis. ECP came later into clinical use for the treatment of refractory glaucoma. ECP is able to specifically target the ciliary epithelium under direct viewing as compared to TCP, which is an indirect cyclodestructive procedure. In the literature, it has been demonstrated that ECP has overall good success with relatively low complication rates when used for adult forms of glaucoma. A new technology using MP-TCP is a promising alternative to conventional cyclophotocoagulation. Early evidence shows that MP-TCP has clinical utility and a good safety profile. Ultrasound cilioplasty is a possible alternative to laser cyclodestruction that is already being commercialized and is currently under investigation. CONCLUSIONS: Both TCP and ECP are effective cyclodestructive procedures and alternatives for the treatment of glaucoma refractory to medical and surgical therapy, though potential for serious complications exists. TCP, ECP, and ultrasound cilioplasty are being used increasingly as the primary surgery for various kinds and stages of glaucoma.


Asunto(s)
Cuerpo Ciliar/cirugía , Cirugía Filtrante/métodos , Glaucoma/cirugía , Presión Intraocular , Fotocoagulación/métodos , Esclerótica/cirugía , Glaucoma/fisiopatología , Humanos , Resultado del Tratamiento
7.
Invest Ophthalmol Vis Sci ; 57(6): 2593-9, 2016 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-27163773

RESUMEN

PURPOSE: To evaluate the relationship between lens position parameters and intraocular pressure (IOP) reduction after cataract surgery in patients with primary open-angle glaucoma (POAG) and in nonglaucomatous patients. METHODS: The main outcomes of this prospective study were percent and absolute IOP change, which were calculated using the preoperative IOP and the IOP 4 months after cataract surgery in POAG and nonglaucomatous eyes. Lens position (LP), defined as anterior chamber depth (ACD) + one-half lens thickness (LT), was assessed preoperatively using parameters from optical biometry. Preoperative IOP, axial length (AL), ACD, LT, relative lens position (RLP), and the ratio of preoperative IOP to ACD (PD ratio) were also evaluated as potential predictors of IOP change. RESULTS: Four months postoperatively, the average IOP reduction was 2.80 ± 3.83 mm Hg (15.79%) from the preoperative mean of 14.73 ± 2.89 mm Hg for nonglaucomatous eyes. The average IOP reduction was 2.66 ± 2.07 mm Hg (16.98%) from the preoperative mean of 14.86 ± 2.97 mm Hg for POAG eyes. Preoperative IOP, sex, AL, ACD, PD ratio, and LP predicted IOP change in nonglaucomatous eyes. Preoperative IOP and PD ratio predicted IOP change in POAG eyes. CONCLUSIONS: Intraocular pressure reduction after phacoemulsification cataract surgery in nonglaucomatous eyes is significantly greater in more anteriorly positioned lenses. Though it did not reach statistical significance in patients with glaucoma, the association of LP with IOP reduction is in the same direction as in nonglaucomatous patients where smaller LP appears to predict greater IOP reduction. Lens position is a simple, easily calculable, accurate, and widely available parameter, which clinicians can potentially utilize in managing glaucoma.


Asunto(s)
Cámara Anterior/patología , Extracción de Catarata , Catarata/complicaciones , Glaucoma de Ángulo Abierto/fisiopatología , Presión Intraocular/fisiología , Lentes Intraoculares , Anciano , Biometría , Femenino , Estudios de Seguimiento , Glaucoma de Ángulo Abierto/complicaciones , Gonioscopía , Humanos , Cristalino/fisiopatología , Masculino , Periodo Posoperatorio , Periodo Preoperatorio , Estudios Prospectivos , Agudeza Visual
8.
Med. leg. Costa Rica ; 23(2): 111-135, sept. 2006. ilus
Artículo en Español | LILACS | ID: lil-585440

RESUMEN

La agresión infantil es un problema social que ha persistido a lo largo de la historia. La problemática abarca lesiones tanto a nivel físico como psicológico. La clínica, en la mayor parte de las veces, es el eje principal en el diagnóstico acertado y el posterior manejo. En este trabajo se analizaron 192 casos de agresión infantil durante el período comprendido entre enero de 2005 y mayo de 2006 y se presentan sus resultados donde la mayoría de los maltratos infantiles incluye abuso sexual, no es común la atención médica luego de la agresión, las víctimas consultan mucho tiempo después y se presentan más casos de maltrato infantil en el mes de Diciembre lo cual podemos asociar con las conductas del mes que suelen ser más irresponsables (fiestas, alcohol, etc.). Es importante que el médico tenga claro los signos de abuso sexual y sus repercusiones tanto físicas como psicológicas ya que es el tipo de agresión más frecuente y muchas veces puede pasar desapercibida.


Child abuse is an issue which has persisted through history. This problem includes not only physical, but psychological damage. Clinical report, most of the times, is the principal axis in the correct diagnosis and the posterior treatment. In this study, 192 cases of child abuse were analyzed between January 2005 and May 2006, and the results presented most of the cases include child molesting, occasional medical attention after the assault, the victims receive medical attention long time after the assault, and most of the cases occur during December, which can be associated with irresponsible behavior (alcohol, parties, etc.). It is very important that the physician is very clear about the signs of sexual abuse and its physical and psychological consequences, since it is the most common type of aggression and in many cases can be unnoticed.


Asunto(s)
Humanos , Masculino , Femenino , Lactante , Preescolar , Niño , Agresión , Niño , Abuso Sexual Infantil , Defensa del Niño , Maltrato a los Niños/psicología , Problemas Sociales , Costa Rica
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