Ciliary Arteries Research Articles

ROLE OF ISCHEMIA IN THE PATHOGENESIS OF DIABETIC VITREOPAPILLARY TRACTION SYNDROME

Objective: to evaluate the role of ischemia in the pathogenesis of diabetic vitreopapillary traction syndrome.Material and methods: The analysis is based on a sample of 30 patients with diabetic vitreopapillary traction syndrome. The study included a standard ophthalmological examination, color doppler mapping, fluorescent angiography. All patients underwent three-port vitrectomy to eliminate traction syndrome.Results: The results of the obtained data indicated that patients with diabetic vitreopapillary traction syndrome had significant changes in the hemodynamics of the eye compared to the normal parameters. А significant difference in a blood flow parameters in the posterior short ciliary arteries system was recorded in eyes with vitreopapillary traction syndrome compaired to paired eyes.Conclusion: The results of the studies indicate that patients with diabetic vitreopapillary traction syndrome have significant changes in regional hemodynamics: a decrease in blood flow velocity in the central retinal artery, posterior short ciliary arteries and an increase in peripheral vascular resistance, which indicates ischemia of the optic nerve head and may also be one of the reasons for the development of vitreopapillary traction.

112° field of view high-resolution swept-source OCT angiography for rat retinas.

This study introduces an ultra-wide field (UWF) and high-resolution swept-source optical coherence tomographic angiography (OCTA) system for rat retinal imaging. Using an asymmetrical optics design, the system achieves unprecedented details of retinal structures and vascular plexuses over a large field of view (112°) in a single-shot acquisition. Views of single-nerve fiber bundles and single capillary vessels are consistently visible over a 112° field of view. The system has a long imaging range and high penetration and allows a full view of vitreous hyaloid vessels, retina, choroid, sclera, and posterior ciliary arteries, down to sub-sclera connective tissues. In a longitudinal study of oxygen-induced retinopathy (OIR) in rats, the system successfully revealed the progression and regression of OIR-related vascular pathologies, such as ischemia, neovascularization, and tortuosity. To our knowledge, this novel UWF-OCT/OCTA prototype designed for rat retinal imaging will be a vital tool for monitoring disease progression and evaluating therapeutic interventions in preclinical models.

Choroidal macrovessel: literature review and analysis of clinical cases

Introduction. Choroidal macrovessel (CM) is a rare anatomical feature most often detected incidentally. Recent studies suggest an arterial origin of CM, with the majority of authors considering it to be an enlarged short posterior ciliary artery. The literature describes both variants of CM not associated with retinal changes and those complicated by exudative manifestations. Purpose. This study aims to describe two clinical cases of choroidal macrovessel and conduct a differential diagnosis based on literature data with clinically similar conditions. Material and methods. Patients underwent a standard ophthalmologic examination, as well as optical coherence tomography, optical coherence tomography angiography (protocols 10 and 20 degrees), and multispectral laser scanning. Results. We present descriptions of two clinical cases: CM in a patient with choroidal folds and a prominent CM with accompanying subretinal fluid. In both cases, CMs were incidental findings not associated with reduced visual acuity. In the second clinical example, we demonstrate the presence of subretinal fluid in a patient with CM, with no negative progression after one year of observation. For differential diagnosis, an analysis of conditions with similar clinical manifestations was conducted based on literature data. Conclusion. The presented clinical cases illustrate the diversity of CM manifestations. In most cases, the pathology is not associated with retinal structural abnormalities; however, it can cause retinal changes in some patients. Due to its rarity, CM can be considered a poorly studied anatomical feature, warranting dynamic observation upon detection.

Non-Arteritic Ischemic Optic Neuropathy

Non-arteritic ischemic optic neuropathy (NAION); it is an optic neuropathy that can cause acute unilateral painless vision loss, optic disc edema, relative afferent pupillary defect, peripapillary hemorrhage and visual field defects in individuals over 50 years of age. Although its pathophysiology has not been fully elucidated today; It is widely accepted that it results from hypoperfusion in the short posterior ciliary arteries that supply the optic nerve head. The diagnosis of NAION is made primarily clinically. While there is no vision loss in approximately one-third of the cases, severe vision loss develops in 40-50%. It is thought that there is always a visual field defect from the beginning of NAION, therefore perimetry is the most important diagnostic test. In the differential diagnosis of NAION, vision- and life-threatening diseases, especially arteritic ischemic optic neuropathy, demyelinating, infiltrative and compressive optic neuropathies, should be considered. Perimetry, blood tests, fluorescein angiography, optical coherence tomography (OCT), OCT angiography, brain and orbital MRI provide very useful information in the differential diagnosis. Although many medical and surgical treatments have been tried, unfortunately there is no effective treatment or prophylactic prevention method for NAION today; However, neuroprotective agents, stem cell and gene therapy treatments aimed at stopping or reducing optic nerve damage appear promising in the near future. The purpose of this review is to provide a comprehensive, up-to-date overview of NAION.

Color Doppler Imaging, Endothelin-1, Corneal Biomechanics and Scleral Rigidity in Asymmetric Age-Related Macular Degeneration.

Age-related macular degeneration (AMD) presents a multifaceted etiopathogenesis involving ischemic, inflammatory, and genetic components. This study investigates the correlation between ocular hemodynamics, scleral rigidity (SR), and plasma endothelin-1 (ET1) levels in treatment-naive patients with asymmetrical AMD. This study included 20 treatment-naive patients (12 females and 8 males) with an average age of 76.4 ± 3.7 years, who presented with AMD with neovascular membrane formation (nAMD) in one eye, and intermediate grade 2 AMD (iAMD) in the other eye. The control group consisted of 20 healthy subjects (13 females and 7 males) with a mean age of 74.7 ± 3.9 years. All patients and healthy controls underwent color Doppler imaging (i) of the ophthalmic artery (OA), short posterior ciliary arteries (SPCAs), and central retinal artery (CRA); Plasma ET-1 levels were measured for all patients and healthy subjects. Corneal biomechanics were assessed using an Ocular Response Analyzer and two indices were obtained: corneal hysteresis (CH) and corneal resistance factor (CRF). Results showed reduced blood flow velocities and increased resistance indices in AMD eyes, particularly affecting the short posterior ciliary arteries. According to mechanical theory, ARMD eyes exhibited elevated scleral rigidity and corneal resistance factor compared to controls, with a notable rise in SR in neovascular AMD (nAMD) eyes. As per the chronic subacute inflammation theory, plasma ET-1 levels were significantly higher in AMD patients, correlating with abnormal SPCAs blood flow and increased resistance indices. Findings suggest a multifactorial etiology of AMD involving an increase of ET-1 plasma levels with biomechanic damages of corneal and scleral tissue in nAMD.

Detailed measurements of the four extraocular rectus muscles’ contribution to the perfusion of the anterior segment of the eye

Background/aimsAnterior segment ischaemia (ASI) is a rare but serious complication of strabismus surgery, which may be caused by damage to the anterior ciliary arteries that run along the rectus muscles....

Investigation of the effects of single and two-muscle horizontal rectus surgeries on macular microvasculature.

To investigate the changes in posterior segment hemodynamics caused by horizontal rectus muscle surgeries using the optic coherence tomography angiography (OCTA). Patients who underwent at least one horizontal rectus recession, resection, or combination surgery were included. The patients were evaluated with an OCTA preoperatively and 30days postoperatively. Postoperative changes in superficial capillary plexus (SCP)-vessel density (VD), deep capillary plexus (DCP)-VD, foveal avascular zone (FAZ) area and choriocapillaris (CC)-flow area parameters were examined. The mean differences (Δ) for the parameters in which significant changes were detected in the whole operated eyes group were compared between the single- and two-muscle surgery groups. Twenty-five eyes of 24 patients with an average age of 16.40 ± 6.75years (5-29) were included. Of the eyes, 10 underwent single muscle recession surgery. Two-muscle surgeries were performed in 15 eyes. SCP-VD in the superior parafoveal region increased significantly postoperatively (53.23 ± 4.11% vs. 54.54 ± 3.67%, p = 0.032). For DCP-VD, there was a statistically significant increase in all zones, except the superior hemisphere and fovea regions (p < 0.05 for all). FAZ area did not change significantly (p = 0.207). There was a significant increase in the CC-flow area (2.171 ± 0.146 mm2 vs. 2.232 ± 0.115 mm2, p = 0.013). There was a significant difference between the two groups only for the Δ SCP-VD/parafovea superior value (-0.62 ± 0.98 vs. 1.57 ± 3.07, p = 0.019). Conventional horizontal rectus muscle surgeries may cause alterations in posterior segment hemodynamics. The number of muscles incised does not seem to greatly affect the magnitude of changes that occur. What is known • After conventional horizontal rectus muscle surgeries, the anterior ciliary arteries are not recanalized, instead, anterior segment blood flow is maintained by increasing the flow in the long posterior ciliary arteries. • Previous studies using Doppler ultrasonography have shown increased flow in the ophthalmic artery, central retinal artery and long posterior ciliary arteries. What is new • In this study, significant increases were observed in superficial and deep capillary plexus-vessel density and choriocapillaris-flow area parameters in the first postoperative month with optic coherence tomography angiography device. • Hemodynamic increases in both retinal and choroidal vasculature were detected in the early period after conventional horizontal rectus muscle surgeries. • The number of muscles incised does not seem to greatly affect the magnitude of changes that occur.

Hydrocortisone treatment as a tool to study conjunctival placode induction.

Conjunctival placodes are a series of placodes that develop into the conjunctival (scleral) papillae and ultimately induce a series of scleral ossicles in the eyes of many vertebrates. This study establishes a hydrocortisone injection procedure (incl. dosage) that consistently inhibits all conjunctival papillae in the embryonic chicken eye. The effects of this hydrocortisone treatment on apoptosis, vasculature, and placode-related gene expression were assessed. Hydrocortisone treatment does not increase apoptotic cell death or have a major effect on the ciliary artery or vascular plexus in the eye. β-catenin and Eda expression levels were not significantly altered following hydrocortisone treatment, despite the absence of conjunctival papillae. Notably, Fgf20 expression was significantly reduced following hydrocortisone treatment, and the distribution of β-catenin was altered. Our study showed that conjunctival papillae induction begins as early as HH27.5 (E5.5). Hydrocortisone treatment reduces Fgf20 expression independently of β-catenin and Eda and may instead affect other members of the Wnt/β-catenin or Eda/Edar pathways, or it may affect the ability of morphogens to diffuse through the extracellular matrix. This study contributes to a growing profile of gene expression data during placode development and enhances our understanding of how some vertebrate eyes develop these fascinating bones.

OCULAR CYSTICERCOSIS: A CASE REPORT

Ocular cysticercosis, though rare, can be extraocular or intraocular. Ocular manifestations usually occur as a part of a systemic infection and can lead to partial or complete visual impairment over a 3-5 y period. The parasite reaches the posterior segment of the eye via the high-flow choroidal circulation through the short ciliary arteries. A 35 y old female patient presented to us with history of blurring of vision in right eye over one week. Fundus examination revealed an oval translucent cyst of about 4 mm in diameter. The patient underwent USG B scan, which revealed well-circumscribed cystic lesion in posterior vitreous.

Dynamics of rheological and biochemical blood parameters of patients with an intermediate stage of the dry form of age-related macular degeneration before and after serum cascade filtration

BACKGROUND: One of the socially significant ophthalmic diseases is the dry form of the age-related macular degeneration, the key feature of which consists in a slowly progressing damage to the pigment epithelium and the formation of drusen. However, the basic mechanisms of pathogenesis are still not completely clear nowadays. AIM: The aim is, using the data of OCT, OCT-angiography and visometry, to study the dynamics of structural and functional parameters of the macular area, as well as the dynamics of rheological and biochemical blood parameters in patients with an intermediate stage of the dry form of age-related macular degeneration before and after the use of serum cascade filtration. MATERIALS AND METHODS: The study included 63 patients (94 eyes) with an intermediate stage of the dry form of age-related macular degeneration. Patients were randomly separated into two groups. The first (main) group consisted of 34 patients (52 eyes), in whom serum cascade filtration was performed; the second group (control) group included 29 patients (42 eyes) who did not receive any specific treatment. In patients of the main group, before and after the serum cascade filtration course (1 month after the start of follow-up), in 6 and 12 months, in addition to standard ophthalmological examination, as an indicator of the efficacy of performed serum cascade filtration, the ultrasound triplex scanning in color Doppler mapping mode with an assessment of blood flow velocity in the posterior short ciliary arteries, Fourier IR spectroscopy, and the testing of the serum and blood viscosity were performed. Patients in the control group also underwent a similar examination at 1, 6, 12 months after the start of follow-up. RESULTS: According to optical coherence tomography, optical coherence tomography-angiography and visometry data, we found a positive dynamics of structural and functional parameters of the macular retina and an improvement in blood rheological parameters with an increase in microcirculation indices against the background of the serum cascade filtration use in treatment of patients with an intermediate stage of the dry form of age-related macular degeneration. At the same time, a statistically significant difference between the two groups begins at 1 month and persists for 12 months of follow-up, being an evidence of the stabilization of the pathological process. CONCLUSIONS: This study showed that after the serum cascade filtration in patients with an intermediate stage of the dry form of age-related macular degeneration, against the background of an improvement in blood rheological and biochemical parameters, there was an improvement in structural and functional parameters of the macular area, which consisted in a decrease of the volume of the drusenoid retinal pigment epithelium detachment and in a visual acuity amelioration.

Role of Posterior Eye Color Doppler in Assessment of Retinopathic Changes in Long Term Type 2 Diabetic Patients

Abstract Background there have been different results in relation to abnormal ocular hemodynamics in the posterior eye (retrobulbar) vessels of patients with diabetic retinopathy (DR). Detection of early signs of retinopathic changes in long-term diabetic patients is urgently needed. Aim of the Work to compare Color Doppler indices of selected posterior eye arteries using Color Doppler sonography in long term type 2 diabetic patients without diagnosed retinopathy and non-diabetic patients. Patients and Methods posterior eye grey scale ultrasound and color Doppler were performed in 60 patients aged 40-70 who had been divided into 2 groups: non-diabetic controls (n = 30), long-term non controlled type 2 diabetic patients (n = 30). The peak systolic velocity (PSV), end-diastolic velocity (EDV), and the resistivity index (RI), of the central retinal artery and posterior ciliary arteries were measured. Results compared with healthy controls, the age-adjusted resistivity indices, PSV and EDV of the posterior ciliary arteries and central retinal artery were lower in patients with long term type 2 diabetes. Conclusion Resistivity index, PSV and EDV alteration of the posterior ciliary arteries and central retinal artery may be prevalent among patients with long term type 2 diabetic patients for prediction of early changes of DR.

Correlation of retrobulbar perfusion deficits with glaucomatous visual field defects.

This study is to evaluate the correlation between retrobulbar perfusion deficits and glaucomatous visual field defects. Eighty-four patients with glaucoma and 17 normal subjects serving as controls were selected. Color Doppler imaging (CDI) was used to measure the changes in blood flow parameters in the retrobulbar ophthalmic artery (OA), central retinal artery (CRA), and short posterior ciliary arteries (SPCAs). Visual field testing was performed using a Humphrey perimeter, categorizing the visual field deficits into four stages according to the Advanced Glaucoma Intervention Study (AGIS) scoring method. Subsequently, the correlation of retrobulbar hemodynamic parameter alterations among glaucomatous patients with varying visual field defects was examined. The higher the visual field stage, the lower the peak systolic velocity (PSV) of the OA, CRA, and SPCAs in glaucomatous patients. The CRA had the highest sensitivity to changes in its PSV. The PSV of the temporal SPCA (TSPCA-PSV) was lower in advanced glaucoma than in early-stage glaucoma. The PSVs of the OA, CRA, and TSPCA, as well as the resistance index of the CRA (CRA-RI), were positively correlated with the visual field index and the mean deviation. Except for that of OA, the PSV of the retrobulbar vessels was negatively correlated with the pattern standard deviation (PSD). The OA-PSV and end-diastolic velocity (EDV) of the CRA and TSPCA were lower in patients with superior visual field defects than in those with inferior visual field defects. Greater severity of visual field defects corresponded to poorer retrobulbar blood flow in glaucomatous patients. Patients suffered significant perfusion impairments in the CRA at the early stage, accompanied by SPCA perfusion disorder at the advanced stage. The presence of a bow-shaped defect in the superior or inferior region of the visual field in moderate-stage glaucoma was closely correlated with retrobulbar vascular EDV. ChiCTR2200059048 (2022-04-23).

Induced magnetic force and curvature effect of ternary hybrid nanofluid (jeffrey model) in ciliary peristaltic channels

ABSTRACT Ternary hybrid nanoparticles require infected blood cell base fluid flow. Blood vessels feature ciliated walls and peristaltic waves. Anemia comes from cancer treatment-induced red blood cell destruction. This study reproduces Jeffrey model blood flow through a ciliary peristaltic artery using ternary hybrid nanoparticles of gold, iron oxide, and copper. This work examines ternary hybrid nanofluid MHD ciliary peristaltic motion using Jeffrey curves. A nonlinear PDE system has heat and induced magnetic force equations. The Adomian Decomposition Method solved this system without long-wavelength approximation. Visualize how essential biological and physical elements affect velocity, temperature, trapping, magnetic force contours, induced magnetic field components, axial pressure, and normal pressure. Flow, temperature, magnetic features, and other important properties are plotted and discussed against biological and biomedical parameters. We discovered full consistency with modest scenario efforts. The increase in nanoparticles gives ternary hybrid nanofluid a larger friction force than hybrid, so its axial pressure gradient at the wall is stronger, decays at hybrid, decays further from nanofluid to base fluid, and reverses at the intermediate area. Peristaltic ciliary activity alters magnetic force contours, shrinks loops, and forms four contour groups with different implications.

Ultrasound indicators of blood flow in the eyes and orbits at different durations of type 1 diabetes mellitus in childhood and adolescence

Diabetic retinopathy is a complication of type 1 diabetes mellitus with high social significance, especially in childhood and adolescence.Aim: To evaluate ultrasound indicators of retrobulbar blood flow at different durations of type 1 diabetes mellitus in childhood and adolescence.Material and Methods. Ultrasound examinations were performed in 70 patients with type 1 diabetes mellitus aged from 5 to 18 years, with disease duration of up to 5 years, from 5 to 10 years, and more than 10 years. The analysis included an assessment of the linear velocity of blood flow and the index of peripheral resistance in the ophthalmic arteries, central arteries and retinal veins, posterior short ciliary arteries, and ophthalmic veins at different times of the duration of type 1 diabetes mellitus.Results. The study revealed a decrease in blood flow velocity in the central retinal arteries, in the posterior short ciliary arteries with an increase in the duration of type1 diabetes mellitus. The greatest decrease in blood flow velocity was recorded in the group with duration of diabetes mellitus of more than 10 years.Conclusion. The obtained data on a decrease in blood flow velocity in the retrobulbar arteries can be used for the assessment and dynamic monitoring of early disorders of the blood supply to the eye and orbit in patients with type 1 diabetes mellitus in childhood and adolescence.

Ocular blood flow in preterm neonates

Retinopathy of prematurity (ROP) is a disorder affecting low birthweight, preterm neonates. In the preterm eye, the retina is not fully developed and neovascularization may occur at the margin between the developed vascular retina and undeveloped avascular retina. Without timely treatment by laser or intravitreal anti-vascular endothelial growth factor (VEGF) therapy, this can lead to tractional retinal detachment and blindness. Visualization of the retina in regular examinations by indirect ophthalmoscopy is hence the current standard of care, but the exams are stressful and interpretation of images is subjective. The upregulation of VEGF in ROP would suggest an increase in ocular blood flow. In this report, we evaluate the potential of ultrafast plane-wave Doppler ultrasound (PWU) to detect increased flow velocities in the orbital vessels supplying the eye in a gentle exam with objective findings. We imaged both eyes of 50 low-birthweight preterm neonates using 18 MHz PWU. Flow velocity in the central retinal artery (CRA) and vein (CRV), and the short posterior ciliary arteries were determined and values at each ROP Stage compared. We found significantly increased velocities in the CRA and CRV in Stage 3 ROP eyes, where intervention would be considered. We compared multivariate models for identifying Stage 3 eyes comprised solely of clinical factors, solely of Doppler parameters, and clinical plus Doppler parameters. The respective models provided areas under their respective ROC curves of 0.760, 0.812, and 0.904. PWU Doppler represents a gentle, objective means for identifying neonates at risk for ROP that could complement ophthalmoscopy.

Spontaneous expulsive choroidal hemorrhage: A rare ocular catastrophe - A case report

Spontaneous expulsive choroidal hemorrhage is described as a sudden accumulation of blood in the potential space between the choroid and sclera, with the source of the blood being the long or short posterior ciliary arteries. It is observed exclusively in the geriatric population with atherosclerotic vessels associated with hypertension.[4] Massive spontaneous choroidal hemorrhage in the absence of surgery or trauma is an infrequent event, described in isolated case reports, and it results in devastating vision loss.[8] We report a case of a 74-year-old patient with uncontrolled hypertension with a sudden loss of vision in the left eye, later diagnosed as spontaneous expulsive choroidal hemorrhage. The patient was treated conservatively with topical steroids, cycloplegics, antibiotics, antiglaucoma medications, and tight bandages with nil visual prognosis. The patient initially refused surgical management and got discharged against medical advice. However, having been mentally prepared, the patient underwent evisceration at a tertiary eye care center nearby.

Uveitis complicated by phthisis bulbi: hemodynamic parameters in the prediction of anterior-posterior eye size reduction

Background. Phthisis bulbi is a serious complication of uveitis, causing vision loss and esthetic defects. Hemodynamic disorders can play an important role in the formation of this complication as a result of uveitis. We did not find data on predicting the progression of phthisis bulbi with a reduction in anterior-posterior size in the available literature. Aim. To analyze the possibility of predicting the reduction in the anterior-posterior size of the eye with uveitis, complicated by phthisis bulbi, based on hemodynamic parameters Materials and Methods. 33 patients aged 5–84 years, of them 19 male and 14 female patients, with unilateral endogenous uveitis, complicated by phthisis bulbi, were examined. 15 patients with uveitis complicated by phthisis bulbi, who had not received any treatment during this time, were examined in dynamics (for at least 1 year). All patients underwent Doppler ultrasound examination of the ophthalmic artery and short posterior ciliary arteries. In addition, all patients underwent biomicroscopic and tonometric examinations, ultrasound biomicroscopy, rheoophthalmography of eyeballs, A-scan and B-scan ultrasonography. The results of the examination of eyes with uveitis complicated by phthisis bulbi were compared with the results of the examination of paired (healthy) eyes of the same patients. Results. We have developed a multiple regression model that allows us to predict a reduction in the anterior-posterior size of the eye with phthisis bulbi due to uveitis. The dynamics of the disease in 15 patients not taking any treatment for uveitis, has been monitored for more than a year. The prediction of phthisis bulbi progression was confirmed in 13 patients, which amounts to 86.7% (p&lt;0.05). Conclusions. We have proposed a model that allows predicting the progressive or stationary course of phthisis bulbi due to uveitis based on hemodynamic parameters. Keywords: infectious uveitis, noninfectious uveitis, phthisis bulbi hemodynamic disorders, anterior-posterior size of the eyeball.

A neural network approach to explore bioelectromagnetics aspects of blood circulation conveying tetra-hybrid nanoparticles and microbes in a ciliary artery with an endoscopy span

Bioelectromagnetics is gaining remarkableness due to its wide-ranging applications in medical and biochemical industries. Our proposed model delves into the bioelectromagnetics aspects of blood circulation in a scenario involving tetra-hybrid nanoparticles and gyrotactic microbes within a ciliated arterial annulus, particularly one mimicking an endoscopic environment. Our model takes into account influential factors, including cilia beating, buoyancy force, heat source, viscous and Joule warming, arterial wall properties, chemical reaction, and bioconvection. Different geometric shapes of suspended tetra-hybrid nanoparticles (spheres, bricks, cylinders, and platelets) are incorporated into the model formation. The close-form solution of the Poisson equation is found in terms of Bessel’s functions. The homotopy perturbation methodology (HPM) is implemented to track down the rapidly convergent series solutions of the highly non-linear coupled flow equations arising. The hemodynamical attributes of distinct evolving factors on the different dimensionless hemodynamic profiles and entities of interest are elucidated evocatively via a sort of graphs and charts. Our results prove that the factors related to electroosmosis have a dual effect on the blood flow pattern. The bloodstream rapidity is alleviated or boosted for the assisting or opposing electroosmosis process. Cooling of blood within the annulus is achieved with a larger cilia length. The Peclet number positively correlates with the gyrotactic microbes’ density. Blood infused with tetra-hybrid nanoparticles exhibits a superior heat transmission rate across the arterial wall compared to others. Additionally, an artificial neural network (ANN) model, developed using HPM-derived data, accurately predicts shearing stress (SS), achieving high accuracy rates of 99.98% in testing and 100% in validation for MB flow. The model’s new findings could be noteworthy for engineers and medical device designers to develop innovative medical devices and technologies based on bioelectromagnetic principles.

Boucher-Neuhauser Syndrome: Chorioretinal Changes in a Single Case Over Time.

To describe chorioretinal changes in a single case of Boucher-Neuhauser Syndrome (BNHS) over 45 years of follow-up. Methods: Retrospective chart review was performed. Color fundus photography from 1977 to 2003 was obtained and digitized. Current fundus photography was obtained with widefield imaging. High-resolution spectral-domain optical coherence tomography (OCT) was performed. Genetic analysis was performed using an inherited retinal disorders panel. Results: Fundus examination demonstrated central chorioretinal atrophy with sclerotic choroidal vessels. Short posterior ciliary arteries became more prominent and tortuous over time. Mid-peripheral atrophy extends to the equator and demonstrates a scalloped pattern with islands of atrophy intervening with areas of normal retina. The far periphery remained minimally affected. High-resolution OCT demonstrated outer retinal atrophy and choriocapillaris loss. Genetic testing showed a homozygous variant for PNPLA6 and a heterozygous variant for TYRP1. Conclusion: Chorioretinal changes in BNHS vary in onset and severity. It is important to diagnose this condition in order to begin timely management of visual and systemic sequelae.

Assessing the impact of internal carotid artery stenosis on choroidal thickness using Cirrus optical coherence tomography

Aims: The choroid, one of the body's most highly vascularized tissues, receives its blood supply from the ophthalmic and posterior ciliary arteries, which stem from the internal carotid artery. The utilization of spectral-domain optical coherence tomography (SD-OCT) for both qualitative and quantitative assessment of the retina is increasing. The recent introduction of enhanced depth imaging OCT (EDI-OCT) has offered a novel approach to evaluate the choroid using commercially accessible SD-OCT devices. EDI-OCT enables the in vivo examination and measurement of the choroid. The main objective of our study is to evaluate choroidal thickness using EDI-OCT in patients with unilateral significant carotid stenosis; the secondary objective is to observe whether hemodynamic changes affect choroidal thickness. Methods: The study is prospectively designed as a cross-sectional, controlled, and single-blind study, encompassing patients who underwent neck computed tomographic angiography within a one-year period due to any disease. Included patients had carotid stenosis of 50% or more on one side and less than 50% on the other side. The eyes on the side with higher carotid stenosis constituted the study group, while the other side formed the control group. Anterior and posterior segment examinations of the patients, visual acuity according to Snellen Chart, and choroidal thickness were measured. Results: A total of 30 eyes of 15 patients were evaluated. Of the patients included in the study, 9 were men and 6 were women; the average age was 67.9 years (49-85). In the study group, the average choroidal thickness measurements were 211 µm in the nasal, 221 µm in the central and 209 µm in the temporal; in the control group, they were measured as 223 µm in the nasal, 243 µm in the central, and 231 µm in the temporal, respectively. Despite the choroidal thickness being thinner in the study group, the difference did not reach statistical significance. Conclusion: Additional research is required to pinpoint the factors contributing to the dynamics of choroidal thickness and to delineate its significance in carotid artery stenosis more comprehensively.