Acoustic Radiation Force Optical Coherence Elastography of the Crystalline Lens: Safety.

Purpose: To assess the safety of acoustic radiation force optical coherence elastography in the crystalline lens in situ.

Methods: Acoustic radiation force (ARF) produced by an immersion single-element ultrasound transducer (nominal frequency = 3.5 MHz) was characterized using a needle hydrophone and used for optical coherence elastography (OCE) of the crystalline lens.

Circulating Adenoid Cystic Carcinoma associated MYB transcripts enable rapid and sensitive detection of metastatic disease in blood liquid biopsies.

Adenoid cystic carcinoma (ACC) is a rare and lethal malignancy that originates in secretory glands of the head and neck. A prominent molecular feature of ACC is the overexpression of the proto-oncogene MYB. ACC has a poor long-term survival due to its high propensity for recurrence and protracted metastasis.

Age dependence of the average refractive index of the isolated human crystalline lens.

We measured the average group refractive index (RI) of 120 isolated lenses from 120 human donors (age: 0.03 to 61 years). The average group RI was calculated from a measurement of the optical thickness of the lens using optical coherence tomography and the apparent window shift of the test chamber caused by the lens.

Effect of compound treatments on mouse lens viscoelasticity.

Previous studies have shown that pharmaceutical agents such as lipoic acid have the ability to soften the lens, presenting a promising avenue for treating presbyopia. One obstacle encountered in the preclinical stage of such agents is the need for precise measurements of lens elasticity in experimental models. This study aimed to evaluate the effects of 25-hydroxycholesterol, lipoic acid, and obeticholic acid on the viscoelastic properties of mouse lenses using a custom-built elastometer system.

Dynamic refraction and anterior segment OCT biometry during accommodation.

Accommodation is the process by which the eye changes focus. These changes are the result of changes to the shape of the crystalline lens. Few prior studies have quantified the relation between lens shape and ocular accommodation, primarily at discrete static accommodation states.

Handheld contact-type OCT and color fundus system for retinal imaging.

We present proof of concept for a handheld contact-type system capable of simultaneous optical coherence tomography (OCT) imaging of the retina and wide-field digital fundus color photography. The study focuses on demonstrating the feasibility of the proposed approach, particularly for eventual use in pediatric patients during examination under anesthesia in the operating room and in the neonatal intensive care unit. Direct contact of the probe with the cornea allows the photographer to maintain a stable position during imaging, reducing motion artifacts in the OCT images.

Peripheral defocus of monofocal intraocular lenses.

Purpose: To quantify the angular dependence of monofocal intraocular lens (IOL) power.

Setting: Ophthalmic Biophysics Laboratory, Kallam Anji Reddy campus, L V Prasad Eye Institute, Hyderabad, India.

Design: Laboratory study.

Estimation of the full shape of the crystalline lens from OCT: validation using stretched donor lenses.

Quantifying human crystalline lens geometry as a function of age and accommodation is important for improved cataract and presbyopia treatments. In previous works we presented as a basis of 3-D functions to represent the full shape of the crystalline lens . Also, we presented the application of to estimate the full shape of the lens from 3-D optical coherence tomography (OCT) images, where only the central part of the lens -visible through the pupil- is available.

Activation of multiple Eph receptors on neuronal membranes correlates with the onset of optic neuropathy.

Background: Optic neuropathy is a major cause of irreversible blindness, yet the molecular determinants that contribute to neuronal demise have not been fully elucidated. Several studies have identified 'ephrin signaling' as one of the most dysregulated pathways in the early pathophysiology of optic neuropathy with varied etiologies. Developmentally, gradients in ephrin signaling coordinate retinotopic mapping via repulsive modulation of cytoskeletal dynamics in neuronal membranes.

Effectiveness of motor and prefrontal cortical areas for brain-controlled functional electrical stimulation neuromodulation.

. Brain-computer interface (BCI)-controlled functional electrical stimulation (FES) could excite the central nervous system to enhance upper limb motor recovery. Our current study assessed the effectiveness of motor and prefrontal cortical activity-based BCI-FES to help elucidate the underlying neuromodulation mechanisms of this neurorehabilitation approach.

Mass spectrometry database of lacrimal gland adenoid cystic carcinoma and normal lacrimal gland tissue identifies extracellular matrix remodeling in these tumors.

Adenoid cystic carcinoma of the lacrimal gland (LGACC) is a slow-growing but aggressive orbital malignancy. Due to the rarity of LGACC, it is poorly understood, which makes diagnosing, treating, and monitoring disease progression difficult. The aim is to understand the molecular drivers of LGACC further to identify potential targets for treating this cancer.

Spatial Transcriptomics Identifies Expression Signatures Specific to Lacrimal Gland Adenoid Cystic Carcinoma Cells.

Although primary tumors of the lacrimal gland are rare, adenoid cystic carcinoma (ACC) is the most common and lethal epithelial lacrimal gland malignancy. Traditional management of lacrimal gland adenoid cystic carcinoma (LGACC) involves the removal of the eye and surrounding socket contents, followed by chemoradiation. Even with this radical treatment, the 10-year survival rate for LGACC is 20% given the propensity for recurrence and metastasis.

Activation of Multiple Eph Receptors on Neuronal Membranes Correlates with The Onset of Traumatic Optic Neuropathy.

Background: Optic neuropathy (ON) is a major cause of irreversible blindness, yet the molecular determinants that contribute to neuronal demise have not been fully elucidated. Several studies have identified 'ephrin signaling' as one of the most dysregulated pathways in the early pathophysiology of ON with varied etiologies. Developmentally, gradients in ephrin signaling coordinate retinotopic mapping via repulsive modulation of cytoskeletal dynamics in neuronal membranes.

Quantification of scleral changes during dynamic accommodation.

The mechanics of accommodation is a complex process that involves multiple intraocular ocular structures. Recent studies suggest that there is deformation of the sclera during accommodation that may also play a role in accommodation, influencing ciliary muscle contraction and contributing to the accommodative response. However, the type and magnitude of the deformations measured varies significantly across studies.

Estimation of the full shape of the crystalline lens from OCT images using .

Quantifying the full 3-D shape of the human crystalline lens is important for improving intraocular lens power or sizing calculations in treatments of cataract and presbyopia. In a previous work we described a novel method for the representation of the full shape of the crystalline lens called , which proved more compact and accurate than compared state-of-the art methods of crystalline lens shape quantification. Here we demonstrate the use of to estimate the full shape of the crystalline lens from optical coherence tomography images, where only the information visible through the pupil is available.

Lens Thickness Microfluctuations in Young and Prepresbyopic Adults During Steady-State Accommodation.

Purpose: To determine whether lens mechanical dynamics change with age and with accommodative demands.

Methods: Lens thickness microfluctuations were measured using a high-speed custom-built spectral domain optical coherence tomography system in five young adults (20 to 25 years old) at 0 diopters (D), 2 D, 4 D, and maximum accommodative demand and in five prepresbyopes (38 to 45 years old) under relaxed and maximal accommodation. For each state, the measurements were repeated four times during the same session.

Characterization of Trabecular Meshwork Mechanical Property Modulation After Application of Lipids.

Treatment of lipids endogenous to the aqueous humor of the eye could serve as a potential therapy to slow the progression of glaucoma. Herein, we describe the method to treat trabecular meshwork samples in vitro with lipids and characterize changes in the samples' stiffness.

Paraxial equivalent of the gradient-index lens of the human eye.

The lens of the eye has a refractive index gradient that changes as the lens grows throughout life. These changes play a key role in the optics of the eye. Yet, the lens is generally simulated using a homogeneous model with an equivalent index that does not accurately represent the gradient.

Periadventitial biomaterials to improve arteriovenous fistula and graft outcomes.

Periadventitial biomaterials have been employed for nearly three decades to promote adaptive venous remodeling following hemodialysis vascular access creation in preclinical models and clinical trials. These systems are predicated on the combination of scaffolds, hydrogels, and/or particles with therapeutics (small molecules, proteins, genes, and cells) to prevent venous stenosis and subsequent maturation failure. Periadventitial biomaterial therapies have evolved from simple drug delivery vehicles for traditional drugs to more thoughtful designs tailored to the pathophysiology of access failure.

A novel edge gradient distance metric for automated evaluation of deformable image registration quality.

Purpose: To develop a new registration quality metric, based on the distance between image edges, for automated evaluation and comparison of DIR algorithms.

Methods: Canny filter is used to create binary gradient images from input images to be compared. A small subregion of one binary image is translated relative to the other.

Automated segmentation of the ciliary muscle in OCT images using fully convolutional networks.

Quantifying shape changes in the ciliary muscle during accommodation is essential in understanding the potential role of the ciliary muscle in presbyopia. The ciliary muscle can be imaged using OCT but quantifying the ciliary muscle shape from these images has been challenging both due to the low contrast of the images at the apex of the ciliary muscle and the tedious work of segmenting the ciliary muscle shape. We present an automatic-segmentation tool for OCT images of the ciliary muscle using fully convolutional networks.

Predictability of pseudophakic refraction using patient-customized paraxial eye models.

Purpose: To determine whether patient-customized paraxial eye models that do not rely on exact ray tracing and do not consider aberrations can accurately predict pseudophakic refraction.

Setting: Bascom Palmer Eye Institute, Miami, Florida.

Design: Prospective study.

Temperature affects the biomechanical response of in vitro non-human primate lenses during lens stretching.

Purpose: To determine the effect of temperature on the accommodative response of non-human primate crystalline lenses during simulated accommodation.

Methods: Eight lenses from 7 cynomolgus monkeys (Macaca fascicularis, ages: 4.5-7.

Combined anterior segment OCT and wavefront-based autorefractor using a shared beam.

We have combined an anterior segment (AS) optical coherence tomography (OCT) system and a wavefront-based aberrometer with an approach that senses ocular wavefront aberrations using the OCT beam. Temporal interlacing of the OCT and aberrometer channels allows for OCT images and refractive error measurements to be acquired continuously and in real-time. The system measures refractive error with accuracy and precision comparable to that of clinical autorefractors.