[Correlation of posterior segment lesions with anterior segment biometric parameters and FBN1 genotype in patients with Marfan syndrome].

Objective: To investigate the characteristics of posterior segment lesions in Marfan syndrome (MFS) patients and their relationship with anterior segment biometric parameters and FBN1 genotype. Methods: A cross-sectional study was conducted. A total of 121 MFS patients, 76 males and 45 females, with an average age of (11.72±11.66) years, who visited the Department of Ophthalmology, Eye & ENT Hospital of Fudan University from January 2013 to March 2023 were included. The presence of posterior scleral staphyloma was observed using B-mode ultrasound, and macular lesions were identified and classified using the atrophy-traction-neovascularization system based on ultra-widefield fundus images, color fundus images, and optical coherence tomography scans. Anterior segment biometric parameters, including axial length of the eye, average corneal curvature, corneal astigmatism, horizontal corneal diameter, anterior chamber depth, and lens thickness, were collected, and the direction and extent of lens dislocation were observed. Molecular genetic analysis of FBN1 gene mutations in patients was performed using next-generation sequencing based on a panel of ocular genetic diseases, and the impact of the genotype and anterior segment biometric parameters on the posterior segment manifestations was analyzed. Results: Sixty patients exhibited posterior segment lesions, including retinal detachment (4 cases, 3.31%), macular lesions (47 cases, 38.84%), and posterior scleral staphyloma (54 cases, 44.63%). There was statistically significant difference in axial length of the eye between patients with and without posterior scleral staphyloma [23.09 (22.24, 24.43) and 27.04 (25.44, 28.88) mm], between patients with and without macular lesions [23.16 (22.24, 24.61) and 27.04 (25.74, 28.78) mm], and between patients with and without atrophic macular lesions [23.16 (22.24, 24.61) and 27.04 (25.74, 28.79) mm] (all P<0.001). There was statistically significant difference in anterior chamber depth between patients with and without macular lesions [3.11 (2.75, 3.30) and 3.34 (3.09, 3.60) mm] (P<0.05). There was also statistically significant difference in corneal astigmatism between patients with and without posterior scleral staphyloma [2.15 (1.20, 2.93) and 1.40 (1.00, 2.20) diopters] (P<0.05). The location and region of the FBN1 gene mutation not only showed statistically significant difference from the positive rates of posterior scleral staphyloma and macular lesions (all P<0.05), but also influenced the occurrence of atrophic macular lesions (both P<0.05). Patients with FBN1 mutations located in the transforming growth factor ß regulatory sequence had the highest proportion of posterior scleral staphyloma and macular lesions (both 10/11). Conclusions: Posterior scleral staphyloma and macular lesions have a relatively high incidence in MFS patients and tend to progress to more severe grades. The age, axial length of the eye, anterior chamber depth, corneal astigmatism, and location and region of the FBN1 gene mutation are factors affecting the posterior segment lesions in MFS patients.

Sex-Specific Differences in the Relationship Between Prematurity and Ocular Geometry.

Purpose: To explore differences in the relationship between gestational age (GA) and birth weight (BW) percentile and ocular geometry between males and females. Methods: The Gutenberg Prematurity Eye Study involved a prospective ophthalmic examination of adults, aged 18 to 52 years, who were born preterm or at term, in Germany. The associations between GA and BW percentile on the main outcome measures were evaluated by uni- and multivariable linear regression analyses. The main outcome measures were central corneal thickness, corneal radius, anterior chamber depth, lens thickness, posterior segment length, and central foveal thickness. Potential sex-specific differences and an effect modification by sex were analyzed. Results: This study involved 438 participants (245 females, 193 males) with an average age of 28.6 ± 8.7 years. In female participants, central foveal thickness was negatively associated with a higher GA (B = -2.99; P < 0.001). Similarly, male participants also demonstrated a negative association between central foveal thickness and GA (B = -4.27; P < 0.001). The multivariable model with effect modification revealed that the central foveal thickness was thicker with lower GA. There was an association between the effect modification of GA with sex and central foveal thickness, demonstrating a more pronounced effect of GA on central foveal thickness in male participants (B = 1.29; P = 0.04). Conclusions: This study identified a sex-specific correlation between lower GA and thicker central foveal thickness, suggesting differences in the developmental trajectory of this biometric parameter concerning GA. A thicker central foveal thickness might affect the visual acuity of individuals born preterm in adulthood, with a more pronounced impact in males and a potential predisposition to age-related diseases later in life. Sex did not influence the association of GA or BW percentile to other ocular geometric parameters.

Evaluation of Long-term Posterior Segment Parameters in Children Who Had Recovered From Multisystem Inflammatory Syndrome.

BACKGROUND AND OBJECTIVE: To evaluate long-term posterior segment findings in children recovering from multisystemic inflammatory syndrome (MIS-C) associated with severe acute respiratory syndrome coronavirus 2. PATIENTS AND METHODS: Our study included 22 patients who were admitted to an intensive care unit with a diagnosis of MIS-C between November 2021 and March 2022, and 25 healthy controls. The study included pediatric patients who had an eye examination an average of 12.35 ± 2.18 months after recovery from MIS-C. Detailed eye examinations and measurements of all participants were obtained retrospectively from patient files. Posterior segment parameters were measured using swept-source optical coherence tomography (OCT) and OCT-angiography (OCT-A); these parameters included peripapillary retinal nerve fiber layer (pRNFL) thickness, central macular thickness (CMT), subfoveal choroidal thickness (SCT), macular vascular densities (VD), and foveal avascular zone (FAZ) area. RESULTS: Mean age was 9.7 ± 3.6 years in the MIS-C group and 10.6 ± 2.8 years in the healthy control group (P = 0.316). There were no statistically significant differences between the MIS-C group and the healthy control group in terms of pRNFL thickness, CMT, and SCT. However, in the MIS-C group, the macular superficial vascular plexus and deep vascular plexus showed significantly lower VD in the superior, inferior, nasal, and temporal quadrants compared to the healthy controls (P < 0.05 for all). A comparison of the superficial and deep FAZ area parameters of both groups showed no statistically significant difference (P > 0.05). CONCLUSIONS: We showed that patients who had recovered from MIS-C had retinal vascular damage at the long-term follow-up. Following up with these patients after recovery with OCT and OCT-A, which are noninvasive methods commonly used in the detailed evaluation of the posterior segment of the eye, could be beneficial for understanding the long-term effects of MIS-C on retinal microvasculature. [Ophthalmic Surg Lasers Imaging Retina 2024;55:518-526.].

Posterior Segment Manifestations of Syphilis and Correlation With Serologic Markers of Infection.

BACKGROUND AND OBJECTIVE: Retrospective analysis correlating serologic titers of ocular syphilis with posterior segment manifestations. PATIENTS AND METHODS: This study consisted of 40 patients (80 eyes imaged, 68 affected) with positive rapid plasma reagin (RPR) and Treponema Pallidum immunoglobulin G. We collected demographic and presentation data including HIV status, absolute CD4 count, RPR, cerebrospinal fluid-venereal disease research laboratory (CSF-VDRL) test, and retinal zone. We categorized imaging into syphilitic outer retinopathy (SOR), acute syphilitic posterior placoid chorioretinopathy, retinitis/chorioretinitis (RC), and papillitis. Multivariate analysis correlated HIV status, RPR, and VDRL titers with posterior segment findings and zone. RESULTS: Mean age of 42.8 ± 10.7 years, with 70% male patients. Presenting visual acuity (logMAR) 0.66 ± 0.74 did not correlate with RPR, nor was it associated with papillitis, RC, or acute syphilitic posterior placoid chorioretinopathy. Higher RPR (≥ 1:128) positively associated with SOR (P = 0.031) and zone 1 (odds ratio [OR], 1.62; P = 0.02), but negatively associated with zone 2 (OR 0.35; P = 0.005). HIV positivity increased RC odds (OR, 4.45; P = 0.047). CONCLUSION: Higher RPR correlated with SOR and zone 1, whereas HIV positivity correlated with RC. [Ophthalmic Surg Lasers Imaging Retina 2024;55:511-516.].

Posterior segment manifestations of Takayasu arteritis: A narrative review.

Ocular symptoms can be the presenting manifestation of Takayasu arteritis (TA) or could be indicative of disease reactivation. A review of published literature related to posterior segment manifestations of TA by using the keywords "Takayasu arteritis," "ophthalmic manifestations," "retina," "retinopathy," "ocular," "optic nerve," and "optic neuropathy" was performed. In total, 62 case reports and 12 case series were included. The majority of the articles were from Asia (n = 47, 64%). Females outnumbered males in the ratio of 7:1. The mean age of patients was 33 years (range: 8-78 years, SD: 13.5 years). In 58% (n = 41 out of 71) cases, ocular symptoms were the presenting manifestation of the underlying disease. Hypotensive retinopathy was found in 70% of eyes, and hypertensive retinopathy was found in 27%. The mean presenting visual acuity (VA) was +1.03 logMAR (range: -0.12 to 3, SD: 1.07), and at the final follow-up was +1.02 logMAR (range: -0.12 to 3, SD 1.17). VA improved in 34% (n = 29/86), remained stable in 45% (39/86), and worsened in 21% (18/86). The mean follow-up was 9 months (range: 0.5-204, SD: 16 months).

LOW VULNERABILITY OF THE POSTERIOR EYE SEGMENT TO SARS-COV-2 INFECTION: Chorioretinal SARS-CoV-2 Vulnerability.

PURPOSE: Retinal manifestations have been described in COVID-19 patients, but it is unknown whether SARS-CoV-2, the causal agent in COVID-19, can directly infect posterior ocular tissues. Here, we investigate SARS-CoV-2 host factor gene expression levels and their distribution across retinal and choroidal cell types. METHODS: Query of single-cell RNA sequencing data from human retina and choroid. RESULTS: We find no relevant expression of two key genes involved in SARS-CoV-2 entry, ACE2 and TMPRSS2, in retinal cell types. By contrast, scarce expression levels could be detected in choroidal vascular cells. CONCLUSION: Given the current understanding of viral host cell entry, these findings suggest a low vulnerability of the posterior eye segment to SARS-CoV-2 with a potential weak spot in the vasculature, which could play a putative causative role in ocular lesions in COVID-19 patients. This may qualify the vasculature of the human posterior eye segment as an in vivo biomarker for life-threatening vascular occlusions in COVID-19 patients.

OPTICAL COHERENCE TOMOGRAPHIC PATTERNS OF POSTERIOR SEGMENT STICKY HEAVY SILICONE OIL.

PURPOSE: To describe unique optical coherence tomography observations of adherent preretinal heavy silicone oil after removal. METHODS: Retrospective observational review of files and optical coherence tomography scans of patients who had pars plana vitrectomy with heavy silicone oil. We investigated the possible precipitating preoperative and intraoperative factors and the association with postoperative epiretinal membrane and cystoid macular edema. RESULTS: Forty-one eyes from 39 patients were involved. Two characteristic sticky silicone oil structures were identified in 33 patients (80%): variably reflective macrodroplets (bubbles) and hyperreflective microdroplets (dots). The main contributing variable was the tamponade duration. Other notable associations included postoperative epiretinal membrane and cystoid macular edema formation. Surgical interventions including heavy liquid did not show a strong predilection to their development. We reported two novel findings of sticky prefoveal macrodroplets in five patients and intravitreal macrodroplets and microdroplets casting shadows on the underlying retina in four patients. CONCLUSION: This study confirms previously reported optical coherence tomography observations of sticky emulsified silicone oil remnants after removal. This is the first report of two distinctly different optical coherence tomography appearances after heavy silicone oil removal. The variability in size and reflectivity may be attributed to the amount and nature of the induced inflammatory reaction.

POSTOPERATIVE POSTERIOR SEGMENT COMPLICATIONS AFTER BOSTON TYPE 1 KERATOPROSTHESIS: Incidence, Risk Factors, and Intermediate-Term Outcomes.

PURPOSE: To identify the incidence of, risk factors for, and outcomes of posterior segment complications (PSC) after Boston Type 1 keratoprosthesis (KPro) implantation. METHODS: Retrospective, consecutive case series of KPro procedures at the Stein Eye Institute. Data regarding ocular history, intraoperative details, postoperative management, and outcomes were collected. Eyes with at least one PSC (PSC group) were compared with eyes without PSC (No PSC group), and risk factors for PSC were determined. RESULTS: Ninety-five PSC occurred in 69/169 eyes (40.8%), at a mean of 20.1 months after KPro implantation (0.01 complications/eye month). The median follow-up after KPro implantation was 44.0 months (range 3.0-174.4). The most common PSC were epiretinal membrane (16.6%), cystoid macular edema (12.4%), vitritis (11.2%), and retinal detachment (9.5%). Previous retinal detachment repair, concomitant intraocular lens removal, postoperative aphakia, and vitritis were risk factors for retinal detachment. Postoperative infectious keratitis was a risk factor for epiretinal membrane, cystoid macular edema, and vitritis. The posterior segment complication group had a significantly higher rate of eyes failing to maintain visual acuity ≥20/200 (HR = 2.28; 95% CI = 1.35-3.85) and KPro retention failure rate (HR = 1.66; 95% CI = 0.95-2.91). CONCLUSION: Posterior segment complications occur in approximately 40% of eyes after KPro implantation, resulting in reduced visual outcomes and KPro retention.

Intraocular pressure and injection forces during intravitreal injection into enucleated porcine eyes.

Injection of biological molecules into the intravitreous humor is of increasing interest for the treatment of posterior segment eye diseases such as age-related degenerative macular degeneration. The injection volume is limited by an increase in intraocular pressure (IOP) and 50-100 µL are typically used for most intravitreally (IVT) applied commercial products. Direct measurement of IOP is difficult and has not been studied dependent on solution properties and injection rates. We used an instrumental set-up to study IOP ex vivo using healthy enucleated porcine eyes. IOP was determined as a function of injection volume for viscosities between 1 and 100 mPas, injection rates of 0.1, 1, and 1.5 mL/min, and needle length and diameter (27/30G and 0.5/0.75″) using Dextran solutions. IOP increased exponentially for injection volumes larger than 100 µL. We did not observe differences in IOP dependent on viscosity, injection rate, and needle diameter. However, variability increased significantly for injection volumes larger than 100 µL and, unexpectedly, declined with higher viscosities. We demonstrate that the exponential increase in IOP is not reflected by injection force measurements for typical configurations that are used for IVT application. The present findings may guide injection volumes for intravitreal injection and inform injection force considerations during technical drug product development.

Long-acting nanoparticle-loaded bilayer microneedles for protein delivery to the posterior segment of the eye.

Treatment of neovascular ocular diseases involves intravitreal injections of therapeutic proteins using conventional hypodermic needles every 4-6 weeks. Due to the chronic nature of these diseases, these injections will be administrated to patients for the rest of their lives and their frequent nature can potentially pose a risk of sight-threatening complications and poor patient compliance. Therefore, we propose to develop nanoparticle (NP)-loaded bilayer dissolving microneedle (MN) arrays, to sustain delivery of protein drugs in a minimally invasive manner. In this research, a model protein, ovalbumin (OVA)-encapsulated PLGA NPs were prepared and optimised using a water-in-oil-in-water (W/O/W) double emulsion method. The impact of stabilisers and primary sonication time on the stability of encapsulated OVA was evaluated using an enzyme-linked immunosorbent assay (ELISA). Results showed that the lower primary sonication time was capable of sustaining release (77 days at 28.5% OVA loading) and improving the OVA bioactivity. The optimised NPs were then incorporated into a polymeric matrix to fabricate bilayer MNs and specifically concentrated into MN tips by high-speed centrifugation. Optimised bilayer MNs exhibited good mechanical and insertion properties and rapid dissolution kinetics (less than 3 min) in excised porcine sclera. Importantly, ex vivo transscleral distribution studies conducted using a multiphoton microscope confirmed the important function of MN arrays in the localisation of proteins and NPs in the scleral tissue. Furthermore, the polymers selected to prepare bilayer MNs and OVA NPs were determined to be biocompatible with retinal cells (ARPE-19). This delivery approach could potentially sustain the release of encapsulated proteins for more than two months and effectively bypass the scleral barrier, leading to a promising therapy for treating neovascular ocular diseases.

QUANTITATIVE TOPOGRAPHIC CURVATURE MAPS OF THE POSTERIOR EYE UTILIZING OPTICAL COHERENCE TOMOGRAPHY.

PURPOSE: Deformations of the retina such as staphylomas in myopia or scleral flattening in high intracranial pressure can be challenging to quantify with en face imaging. We describe an optical coherence tomography-based method for the generation of quantitative posterior eye topography maps in normal and pathologic eyes. METHODS: Using "whole eye" optical coherence tomography, we corrected for subjects' optical distortions to generate spatially accurate posterior eye optical coherence tomography volumes and created local curvature (KM, mm-1) topography maps for each consented subject. We imaged nine subjects, three normal, two with myopic degeneration, and four with papilledema including one that was imaged longitudinally. RESULTS: Normal subjects mean temporal KM was 0.0923 mm-1, nasal KM was 0.0927 mm-1, and KM local variability was 0.0162 mm-1. In myopic degeneration, subjects KM local variability was higher at 0.0836 mm-1. In papilledema subjects nasal KM was flatter compared with temporal KM (0.0709 vs. 0.0885 mm-1). Mean intrasession KM repeatability for all subjects was 0.0036 mm-1. CONCLUSION: We have developed an optical coherence tomography based method for quantitative posterior eye topography that offers the ability to analyze local curvature with micron scale resolution and offers the potential to help clinicians and researchers characterize subtle, local retinal deformations earlier in patients and follow their development over time.

Prognostic Factors for Axial Length Elongation and Posterior Staphyloma in Adults With High Myopia: A Japanese Observational Study.

PURPOSE: To identify prognostic factors for axial length (AL) elongation and incidence of posterior staphyloma (PS) in adult Japanese patients with high myopia. DESIGN: Retrospective, observational cohort study. METHODS: Six-year follow-up data for 345 patients (620 eyes with AL ≥ 26.5 mm and spherical equivalent [SE] ≤- 8.00 diopters) admitted to the Tokyo Medical and Dental University Hospital from 2007 to 2017 were analyzed retrospectively. Main outcome measures were change in AL from baseline, factors associated with AL, categorization of eyes with high myopia, factors associated with incidence of PS, and impact of PS on myopic maculopathy and visual function. RESULTS: The mean annual increase in AL was 0.03 mm. Presence of optic nerve disc conus (P = .025), steeper corneal curvature, lower SE, and decreased choroidal thickness (CT) (all P < .001) were associated with increased AL in univariate and multivariate analyses. Younger age (P = .003) and no use of intraocular pressure-lowering medications (P = .046) were associated with increased AL. Eyes with high myopia were categorized using factor analysis as associated with glaucoma, severe pathologic myopia, and mild-to-moderate pathologic myopia. Older age, increased AL, glaucoma, and choroidal thinning (all P ≤ .001) were identified as significant risk factors for the incidence of PS in univariate and/or multivariate analyses. Incidence of PS was a precursor for myopic maculopathy and visual field defects. CONCLUSIONS: Optic nerve disc conus, steeper corneal curvature, lower SE, decreased CT, and no use of intraocular pressure-lowering medications were prognostic factors for increased AL. Older age, increased AL, glaucoma, and decreased CT were prognostic factors for PS.

Posterior Segment Ocular Parameters in Children with Familial Mediterranean Fever.

Purpose: To measure and compare posterior ocular layers in remission period in children with familial Mediterranean fever (FMF).Methods: A randomly selected eye and fellow eye of 20 FMF patients and 20 control eyes were evaluated. The average age of patients and control subjects were 12.9 ± 2.7 and 13.4 ± 2.7, respectively (p = .57). Peripapillary retinal nerve fiber layer thickness, optic nerve head parameters, macular ganglion cell inner plexiform layer and ganglion cell complex thickness, foveal and parafoveal vascular densities, superficial/deep foveal avascular zone area and choroidal thickness were measured using swept source optical coherence tomography angiography.Results: Among the overall measurements, temporal quadrant parafoveal vessel density of patients was significantly higher than that of controls (49.20 ± 2.57% vs 47.14 ± 3.17%, p = .04) and nasal quadrant vessel density was lower (42.88 ± 4.13% vs 46.76 ± 3.18%, p = .02).Conclusions: This study indicated that FMF as an autoimmune disease may affect foveal vascular structure in children besides multiple other organ involvement.

Ocular pathology in NeuroAIDS - An autopsy study.

The central nervous system (CNS) and the eye are involved in Human immunodeficiency virus related disease. Although, optic nerve is considered an extension of the CNS, it has not been systematically evaluated to determine if infections of brain can extend into the eye or vice versa. The brain and posterior compartment of eyeball retrieved at autopsy of patients succumbing to NeuroAIDS, were evaluated with Hematoxylin & Eosin, special stains and immunohistochemistry for infective pathogens. Multiplex PCR was performed in vitreous, CSF and serum for simultaneous detection of bacterial, viral, and protozoal opportunistic infections. Ocular involvement in NeuroAIDS was seen in 93.7% (15/16) with opportunistic infection being the most common 62.5% (10/16); with toxoplasma optic neuropathy in 5 (50%), Cryptococcal optic neuritis in 3 (30%), and Cytomegalovirus chorioretinitis in 2 (20%). Concordance between ocular and CNS pathology was seen in 50% of cases. CSF PCR was more sensitive than PCR in vitreous for detecting ocular infections in posterior compartment of eye.

Micelles: Promising Ocular Drug Carriers for Anterior and Posterior Segment Diseases.

Micelles have been studied in the targeting of drug substances to different tissues as a nano-sized delivery system for many years. Sustained drug release, ease of production, increased solubility, and bioavailability of drugs with low water solubility are the most important superiorites of micellar carriers. These advantages paved the way for the use of micelles as a drug delivery system in the ocular tissues. The unique anatomical structure of the eye as well as its natural barriers and physiology affect ocular bioavailability of the drugs negatively. Conventional dosage forms can only reach the anterior segment of the eye and are used for the treatment of diseases of this segment. In the treatment of posterior segment diseases, conventional dosage forms are administered sclerally, via an intravitreal injection, or systemically. However, ocular irritation, low patient compliance, and high side effects are also observed. Micellar ocular drug delivery systems have significant promise for the treatment of ocular diseases. The potential of micellar systems ocular drug delivery has been demonstrated by in vivo animal experiments and clinical studies, and they are continuing extensively. In this review, the recent research studies, in which the positive outcomes of micelles for ocular targeting of drugs for both anterior and posterior segment diseases as well as glaucoma has been demonstrated by in vitro, ex vivo, or in vivo studies, are highlighted.

Association of Long-Duration Spaceflight With Anterior and Posterior Ocular Structure Changes in Astronauts and Their Recovery.

Importance: During long-duration spaceflights, nearly all astronauts exhibit some change in ocular structure within the spectrum of spaceflight-associated neuro-ocular syndrome. Objective: To quantitatively determine in a prospective study whether changes in ocular structures hypothesized to be associated with the development of spaceflight-associated neuro-ocular syndrome occur during 6-month missions on board the International Space Station (ISS). Design, Setting, and Participants: The Ocular Health ISS Study of astronauts is a longitudinal prospective cohort study that uses objective quantitative imaging modalities. The present cohort study investigated the ocular structure of 11 astronauts before, during, and after a 6-month mission on board the ISS. Main Outcomes and Measures: Changes in ocular structure (peripapillary edema, axial length, anterior chamber depth, and refraction) hypothesized to be associated with the development of spaceflight-associated neuro-ocular syndrome during 6-month missions on board the ISS were assessed. Statistical analyses were conducted from August 2018 to January 2019. Results: Before launch, the 11 astronauts were a mean (SD) age of 45 (5) years, a mean (SD) height of 1.76 (0.05) m, and a mean (SD) weight of 75.3 (7.1) kg. Six astronauts did not have prior spaceflight experience, 3 had completed short-duration missions on board the Space Shuttle, and 2 had previous long-duration spaceflight missions on board the ISS. Their mean (SD) duration on board the ISS in the present study was 170 (19) days. Optic nerve head rim tissue and peripapillary choroidal thickness increased from preflight values during early spaceflight, with maximal change typically near the end of the mission (mean change in optic nerve head rim tissue thickness on flight day 150: 35.7 µm; 95% CI, 28.5-42.9 µm; P < .001; mean choroidal thickness change on flight day 150: 43 µm; 95% CI, 35-46 µm; P < .001). The mean postflight axial length of the eye decreased by 0.08 mm (95% CI, 0.10-0.07 mm; P < .001) compared with preflight measures, and this change persisted through the last examination (1 year after spaceflight: 0.05 mm; 95% CI, 0.07-0.03 mm; P < .001). Conclusions and Relevance: This study found that spaceflight-associated peripapillary optic disc edema and choroid thickening were observed bilaterally and occurred in both sexes. In addition, this study documented substantial peripapillary choroid thickening during spaceflight, which has never been reported in a prospective study cohort population and which may be a contributing factor in spaceflight-associated neuro-ocular syndrome. Data collection on spaceflight missions longer than 6 months will help determine whether the duration of the mission is associated with exacerbating these observed changes in ocular structure or visual function.

Ocular Complications in School-Age Children and Adolescents after Allogeneic Bone Marrow Transplantation.

PURPOSE: To determine the ocular complications in school-age children and adolescents surviving at least 1 year following allogeneic bone marrow transplantation. DESIGN: Retrospective cohort study. METHODS: In this institutional study, 162 patients (7-18 years old) met our inclusion criteria with a mean age of 13.4 years at bone marrow transplantation. Follow-up ranged from 13 months to 12 years (mean 4 years; median 3.2 years). Patient charts were screened for cataract formation, dry eye, and other anterior and posterior segment diseases. RESULTS: Cataract formation was noted in 57 patients. Univariate analysis showed that fractionated total body irradiation, race, and use of cytarabine significantly increased the incidence of cataract formation (P < 0.05). Multivariate analysis of significant variables showed that total body irradiation was a risk factor for cataract formation. Of the 57 patients (97 eyes) who developed cataracts after bone marrow transplantation, 4 patients (6 eyes) required cataract surgery. After surgery, all patients had visual acuities of 20/20 to 20/25. Of the 162 patients, 51 developed dry eyes. Univariate analysis showed that age at transplantation; steroid use, chronic graft-versus-host disease; use of fludarabine, melphalan, and thiotepa; and receiving no pre-transplantation conditioning regimen prior to bone marrow transplant significantly increased the risk of dry eye syndrome (P < 0.05). In multivariate analysis, chronic graft-versus-host disease was a significant risk factor for dry eye syndrome. CONCLUSIONS: Due to the high incidence of cataract formation and dry eye disease in this population, this study proposes these patients be screened using examinations by a pediatric or general ophthalmologist at least every year.

Ocular changes in traumatic brain injury: A review.

Traumatic brain injury is represented by a penetrating or non-penetrating head injury, which causes disruption in the normal functioning of the brain. Traumatic brain injury has been an ardently debated topic of discussion due to its prevalence in media centric persons such as military personnel and athletes. Current assessments for traumatic brain injury have looked at vestibulo-ocular and vascular parameters to aid in diagnosis. Innovations in non-invasive ophthalmic imaging have allowed for the visualization of specific tissue structure/function relationships in a variety of ophthalmic and neurodegenerative diseases. As the eye and brain share significant embryological and physiological pathways, ocular imaging modalities may provide a novel and impactful tool in advancing assessment of traumatic brain injury. Herein, we examined the available literature and data on visual fields, mean retinal nerve fiber layer thickness, retinal ganglion cell layer thickness, and cerebral blood flow following traumatic brain injury. This review of published individual and population-based studies was performed in order to explore the feasibility and importance of considering ocular imaging biomarkers following traumatic brain injury.