Ophthalmic changes in a spaceflight analog are associated with brain functional reorganization.

Following long-duration spaceflight, some astronauts exhibit ophthalmic structural changes referred to as Spaceflight Associated Neuro-ocular Syndrome (SANS). Optic disc edema is a common sign of SANS. The origin and effects of SANS are not understood as signs of SANS have not manifested in previous spaceflight analog studies. In the current spaceflight analog study, 11 subjects underwent 30 days of strict head down-tilt bed rest in elevated ambient carbon dioxide (HDBR+CO2 ). Using functional magnetic resonance imaging (fMRI), we acquired resting-state fMRI data at 6 time points: before (2), during (2), and after (2) the HDBR+CO2 intervention. Five participants developed optic disc edema during the intervention (SANS subgroup) and 6 did not (NoSANS group). This occurrence allowed us to explore whether development of signs of SANS during the spaceflight analog impacted resting-state functional connectivity during HDBR+CO2 . In light of previous work identifying genetic and biochemical predictors of SANS, we further assessed whether the SANS and NoSANS subgroups exhibited differential patterns of resting-state functional connectivity prior to the HDBR+CO2 intervention. We found that the SANS and NoSANS subgroups exhibited distinct patterns of resting-state functional connectivity changes during HDBR+CO2 within visual and vestibular-related brain networks. The SANS and NoSANS subgroups also exhibited different resting-state functional connectivity prior to HDBR+CO2 within a visual cortical network and within a large-scale network of brain areas involved in multisensory integration. We further present associations between functional connectivity within the identified networks and previously identified genetic and biochemical predictors of SANS. Subgroup differences in resting-state functional connectivity changes may reflect differential patterns of visual and vestibular reweighting as optic disc edema develops during the spaceflight analog. This finding suggests that SANS impacts not only neuro-ocular structures, but also functional brain organization. Future prospective investigations incorporating sensory assessments are required to determine the functional significance of the observed connectivity differences.

Analysis of the Peripapillary Choroidal Vascular Characteristics in Papilledema Associated with Pseudotumor Cerebri.

SIGNIFICANCE: Choroidal vascularity index measured by image binarization method from peripapillary optical coherence tomography sections has been found significantly lower in papilledema patients than healthy controls. PURPOSE: The purpose of this study was to compare peripapillary choroidal parameters in papilledema patients with control subjects. METHODS: Peripapillary spectral domain optical coherence tomography scans of 34 patients with papilledema and 34 healthy controls are acquired for the study. Images are binarized with the ImageJ software (National Institutes of Health, Bethesda, MD) to calculate total choroidal area, stromal area, luminal area, and choroidal vascularity index. RESULTS: Total choroidal area, luminal area, and choroidal vascularity were significantly lower in papilledema patients compared with healthy controls on right (1.343 ± 0.286 vs. 1.694 ± 0.344, P < .001; 0.880 ± 0.209 vs. 1.167 ± 0.255, P < .001; 65.28 ± 2.99% vs. 68.68 ± 2.81%, P < .001, respectively) and left eyes (1.376 ± 0.308 vs. 1.647 ± 0.339, P < .001; 0.899 ± 0.231 vs. 1.134 ± 0.237, P < .001; 64.92 ± 3.44 vs. 68.84 ± 3.23, P < .001, respectively). No difference was found between active and remitted stages of papilledema in terms of choroidal parameters. CONCLUSIONS: Peripapillary total choroidal area, luminal area, and choroidal vascularity index are significantly reduced in patients with papilledema. These parameters might be beneficial tools for evaluating choroidal vascularity in papilledema quantitatively and differential diagnosis for optic disc edema.

Correlation Between Optic Disc Peripapillary Capillary Network and Papilledema Grading in Patients With Idiopathic Intracranial Hypertension: A Study of Optical Coherence Tomography Angiography.

BACKGROUND: The continued increase in idiopathic intracranial hypertension (IIH) prevalence has many implications for societal health care. Its potential vision-threatening consequences make ophthalmologists key players in its diagnosis and management. Newer technology such as optical coherence tomography angiography (OCT-A) enables evaluation of the branching complexity of the peripapillary capillary plexus, a region where accurate imaging via fluorescein angiography was previously limited. METHODS: A cross-sectional, observational study of 23 (46 eyes) consecutive patients with IIH. Peripapillary total vasculature was recorded using commercial OCT-A en face vessel density mapping. In addition, OCT-A blood flow slab was compared with papilledema grading. OCT-A images were analyzed using a customized image analysis protocol using ImageJ software (v1.51w) and Photoshop software (Adobe Systems, CA). SPSS software version 25 was used for statistical analysis (SPSS Inc, IBM, Chicago, IL). RESULTS: Skeletonized vessel density peripapillary capillary plexus was significantly associated with Frisen papilledema grades, OCT retinal nerve fiber layer (RNFL), and macular ganglion cell layer (GCL) thickness with a P < 0.001, P = 0.022, and P = 0.006, respectively. Every point increase in grade was correlated with a decrease of 9.1 pixels/mm2 in vessel density (R = 0.512, ß = -0.115 ± 0.029; P < 0.001). Increased papilledema was correlated with an increased retinal blood flow percentage (R = 0.300, ß = 2.114 ± 1.013; P < 0.05) and decreased choroidal blood flow (CBF) percentage (R = 0.300, ß = 2.114 ± 1.013; P < 0.05). Every point increase in grade was correlated with a decrease in CBF by 47.4%, as calculated using a linear best-fit line inclusive for all of the data points. CONCLUSIONS: OCT-A allows for effective visualization and quantification of the peripapillary retinal vasculature. Our results demonstrate a correlation between skeletonized peripapillary density and papilledema grading, OCT RNFL thickness, and GCL thickness. In addition, we show a significant negative correlation between CBF and papilledema grading. These changes provide key findings regarding the pathophysiology of optic neuropathy in papilledema and highlight the potential of OCT-A as a diagnostic tool for papilledema and a clinical marker for detecting early optic nerve damage.

Evaluation of the patients diagnosed as idiopathic intracranial hypertension with and without papilledema visual pathways by analysis of visual evoked potential.

Background Idiopathic intracranial hypertension (IIH) is a clinical syndrome characterized by increased intracranial pressure in the absence of clinical, laboratory, or radiological findings of space-occupying lesion in the cranium. Papilledema is found in majority of the patients with IIH while it is absent in only about 5-6% of the patients. Methods Our primary objective was to evaluate the patients with IIH with (n: 45) and without (n: 15) papilledema using cranial MRI and VEP analyses and to compare the obtained results. Diagnosis of IIH according to ICHD-3 criteria admitted to and followed in our clinic before receiving any treatment between 2008 and 2018 were reviewed retrospectively after obtaining approval from the Ethics Committee. Results There was no statistically significant difference between both groups' ages (P: 0.494) while differences in lumbar puncture (LP) opening pressure and VAS were found to be statistically significant (p = 0.034, 0.001, respectively). In our VEP investigation, it was seen that latencies in the group without papilledema were seen to be closer to those in the control group (P latency: 0.706, P amplitude: 0.080). Increase in latency and decrease in amplitude were seen in the group with papilledema compared to the group without papilledema (p < 0.001). Conclusion In conclusion, alterations in the optic nerve may be detected with VEP investigation before the detection of papilledema through ophthalmoscopic examination in these patients. Thus, VEP investigation may be considered to have predictive value. VEP examination may be recommended in diagnosis and treatment and during follow-up periods.

Highlights Clinical imaging (cranial MRI-MR-angiography-venography) and VEP analyses were evaluated comparatively with detail in the patients with and without papilledema. In the literature, there are studies on VEP analysis. They have been done on acute and chronic stages of idiopathic intracranial hypertension. In the present study, the patients with and without papilledema were compared in contrast to other studies. Increased VEP latency was seen in both groups being especially more prominent in the group with papilledema.

Idiopathic Intracranial Hypertension: Glymphedema of the Brain.

BACKGROUND: During the last decade, our understanding of cerebrospinal fluid (CSF) physiology has dramatically improved, thanks to the discoveries of both the glymphatic system and lymphatic vessels lining the dura mater in human brains. EVIDENCE ACQUISITION: We detail the recent basic science findings in the field of CSF physiology and connect them with our current understanding of the pathophysiology of idiopathic intracranial hypertension (IIH). RESULTS: Transverse sinus (TS) stenoses seem to play a major causative role in the symptoms of IIH, as a result of a decrease in the pressure gradient between the venous system and the subarachnoid space. However, the intracranial pressure can be highly variable among different patients, depending on the efficiency of the lymphatic system to resorb the CSF and on the severity of TS stenoses. It is likely that there is a subclinical form of IIH and that IIH without papilledema is probably under-diagnosed among patients with chronic migraines or isolated tinnitus. CONCLUSIONS: IIH can be summarized in the following pathological triad: restriction of the venous CSF outflow pathway-overflow of the lymphatic CSF outflow pathway-congestion of the glymphatic system. To better encompass all the stages of IIH, it is likely that the Dandy criteria need to be updated and that perhaps renaming IIH should be considered.

Retinal Manifestations of Idiopathic Intracranial Hypertension.

TOPIC: This review presents a case series and systematic review to understand retinal changes in patients with idiopathic intracranial hypertension (IIH) using fundus photography and OCT. CLINICAL RELEVANCE: IIH is a condition of raised intracranial pressure of unknown cause, usually observed in young, obese women. Ophthalmologic manifestations of IIH such as papilledema and abducens nerve palsy are well recognized, but less common retinal manifestations may occur. METHODS: A retrospective institutional chart review (July 2018-March 2020) was performed on consecutive IIH patients. Fundus photographs were obtained followed by neuro-ophthalmology assessment to elicit clinical characteristics and for diagnosis. Patients who met the modified Dandy criteria were included. A systematic review of observational studies was conducted using Ovid MEDLINE and EMBASE to November 17, 2019, to supplement the case series data. RESULTS: Of 144 consecutive IIH clinical patients reviewed, 10 (6.9%) and over 182 patients from the literature showed retinal findings (% in case series, % in literature, respectively): subretinal fluid (SRF; 30,9), chorioretinal folds (30,68), macular exudate (ME; 20,5), choroidal neovascular membrane (CNVM; 10,15), venous stasis retinopathy (VSR; 10,2), choroidal infarction (0,1), and branch retinal artery occlusion (BRAO; 0,1). Eight clinical patients were women (80%), average age was 32.00 ± 13.99 years, body mass index was 40.63 ± 7.43 kg/m2, baseline visual acuity (VA) was 0.79 ± 0.30 in both eyes, and visual field (VF) results were -9.89 ± 11.52 dB in both eyes. Among clinical patients, 2 (1 with SRF, 1 with CNVM) had distinctive retina-related VF defects at presentation. Outer retinal abnormalities persisted on OCT in patients after resolution of SRF and papilledema. Surgical treatment (peritoneal shunt) was required for 2 patients (1 with VSR, 1 with SRF); others were treated with weight loss and acetazolamide alone. The patient with significant ME had hypertension that was treated. DISCUSSION: Significant retinal manifestations associated with IIH include CNVM, ME, SRF, VSR, chorioretinal folds, choroidal infarction, and BRAO. These may reduce VA or cause VF defects unrelated to papilledema, emphasizing the importance of a detailed dilated fundus examination. Consultation with a retina specialist is advised in patients with peripapillary CNVM.

Use of En Face Optical Coherence Tomography to Monitor Papilledema in Idiopathic Intracranial Hypertension: A Pilot Study.

BACKGROUND: En face optical coherence tomography (OCT) uses the data acquired during OCT of the optic disc, which typically is used to determine measurements of the peripapillary retinal nerve fiber layer (ppRNFL), to generate a coronal composite fundus image rather than a cross-sectional image. En face OCT has been reported to identify retinal changes related to papilledema in idiopathic intracranial hypertension (IIH) but has not been evaluated for monitoring papilledema. This study aimed to assess the reliability and validity of en face OCT for monitoring papilledema. METHODS: Using the Pearson correlation coefficient (R), these measurements were compared with ppRNFL thickness as well as average diameter and estimated area. Four fellowship-trained neuro-ophthalmologists were asked to qualitatively rank en face images by the area of optic disc edema while masked from all other clinical data. Rankings were compared with ppRNFL thickness as a gold standard and with en face OCT characteristics using the Pearson correlation coefficient (R). RESULTS: Experts were able to correctly identify an increase in average ppRNFL thickness >10 µm with a mean (SD) of 91% (±7%) accuracy. A ranking error among experts corresponded to a mean (standard error) change in the ppRNFL thickness of 6 (±6) µm. The mean Pearson correlation coefficient by the area of disc edema among experts was 0.92 (±0.13). CONCLUSIONS: Multiple objective parameters of en face OCT of optic disc edema have an excellent correlation with ppRNFL thickness. These results suggest that en face OCT is a valid clinical tool for monitoring papilledema in IIH.

Intravitreal Steroid Treatment for Uveitis Associated with Dabrafenib and Trametinib for Metastatic Cutaneous Melanoma.

Purpose: To report a case of bilateral retinal inflammation under long-term therapy with dabrafenib/trametinib for metastatic cutaneous melanoma.Methods: Retrospective chart review.Results: A 59-year-old patient with metastatic cutaneous melanoma diagnosed in 2004 under treatment with dabrafenib/trametinib since 2014 presented to our department with intraretinal hemorrhage and extrafoveal macula edema on the right eye and optic disc swelling on the left eye. The patient did not report visual complaints. After cessation of dabrafenib/trametinib and subconjunctival and intravitreal corticosteroid injections, optic disc swelling on the left eye recovered after 6 months. The macula edema on the right eye was treated with one intravitreal anti-VEGF (vascular endothelial growth factor) injection after encroaching upon the fovea 10 months after initial presentation. The final visual acuity was 20/20 on both eyes.Conclusion: Even after years of treatment with low dose dabrafenib/trametinib, ocular toxicity can develop. Such cases can respond well to intravitreal corticosteroids.

Updates on ophthalmic imaging features of optic disc drusen, papilledema, and optic disc edema.

PURPOSE OF REVIEW: Optic nerve head elevation can be associated with vision loss. This review provides an update regarding key features of optic disc drusen (ODD) compared with papilledema from increased intracranial pressure and optic disc edema from other causes. RECENT FINDINGS: Clinical history and funduscopic examination are not sufficient to correctly diagnose different causes of optic nerve head elevation. Multimodal ophthalmic imaging is noninvasive and should be used as first-line diagnostic testing to distinguish optic disc edema or papilledema from pseudoedema. Advanced ophthalmic imaging, including enhanced depth imaging optical coherence tomography (EDI-OCT) and autofluorescence imaging, can visualize ODD at high resolution and determine whether there is optic disc edema. OCT angiography does not require contrast and can rapidly visualize papillary, peripapillary, and macular microvasculature and identify important vascular biomarker of ischemia and, potentially, visual prognosis. SUMMARY: Multimodal ophthalmic imaging can help in the diagnosis of ODD and optic disc edema and identify patients at high risk of vision loss and neurological issues in order to ensure appropriate diagnosis and treatment.

Clinical Characteristics of Idiopathic Intracranial Hypertension in Patients Over 50 Years of Age: A multicenter clinical cohort study.

PURPOSE: To characterize the clinical features of idiopathic intracranial hypertension (IIH) in patients >50 years of age compared to the typical IIH population and existing data for this older cohort. DESIGN: Retrospective, clinical cohort study. METHODS: Medical records of 65 patients >50 years of age at first diagnosis of IIH were reviewed based on the Modified Dandy Criteria from 4 academic centers. Each center provided randomly selected controls from IIH patients <50 years of age for each study patient at their location. Data recorded included patient demographics, presenting symptoms, medications, coexisting medical conditions, cerebrospinal fluid (CSF) opening pressure, treatments, and neuro-ophthalmic data from initial and final visits. RESULTS: Compared to controls, the older cohort showed the following characteristics: fewer females (n = 51 [78.5%] vs. controls: n = 60 [92.3%]; P = .045), fewer headaches (n = 33 [50.8%] vs. controls: 52 [80.0%]; P = .001), more frequent incidental discoveries of papilledema (n = 19 [29.2%] vs. controls: 7 [10.8%]; P = .015), and lower CSF opening pressure [median: 33 cm H2O [range: 21-58 cm H2O] vs. the median for controls: 34 cm H2O [range: 24-67 cm H2O; P = .029). CONCLUSIONS: Patients with IIH diagnosed at >50 years of age were less often female and had lower CSF opening pressure, fewer headaches, a higher chance of incidentally identified papilledema, and body mass index similar to that of younger IIH patients. Older IIH onset was not associated with worse visual outcome.

Pilocytic astrocytoma, another way to reach your diagnosis / Astrocitoma pilocítico, outra forma de chegar ao seu diagnóstico

Abstract Cerebellar astrocytoma (low-grade glioma) is the most frequent tumor of the Central Nervous System in pediatric age, corresponding to 10-20% of brain tumors, having its maximum incidence at 5 years. Brain tumors are the second cause of death at this age, behind leukemias. Its most frequent clinic is headache with vomiting which can worsen in the morning and awaken the patient at night. The most frequent ophthalmological clinic is papilledema and involvement of the cranial nerve VI. In our case we present an atypical presentation (cranial IV), in which a quick derivation favored a better prognosis.

Resumo O astrocitoma cerebelar (glioma de baixo grau) é o tumor mais frequente do Sistema Nervoso Central em idade pediátrica, correspondendo a 10-20% dos tumores cerebrais, tendo sua incidência máxima em 5 anos. Os tumores cerebrais são a segunda causa de morte nesta idade, atrás das leucemias. Sua clínica mais frequente é a cefaleia com vômitos que podem piorar pela manhã e despertar o paciente à noite. A clínica oftalmológica mais frequente é o papiledema e o envolvimento do nervo craniano VI. Em nosso caso apresentamos uma apresentação atípica (IV craniana), em que uma derivação rápida favoreceu um melhor prognóstico.

Effect of Shunting on Visual Outcomes and Headache in Patients with Idiopathic Intracranial Hypertension.

BACKGROUND: Visual dysfunction and headache are major symptoms in patients with idiopathic intracranial hypertension (IIH). We aimed to evaluate the improvement of these symptoms in patients who underwent ventriculoperitoneal (VPS) and lumboperitoneal (LPS) shunting. METHODS: Electronic medical records were reviewed to identify baseline and treatment characteristics for patients diagnosed with IIH over 10 years. Visual outcomes and headache were evaluated at the latest follow-up post shunting. RESULTS: We included 163 patients with a mean age of 32.6 years. Most patients (74.2%) underwent VPS versus 25.8% of patients who received LPS. After a mean follow-up duration of 35 months, there was a 58.3% decrease in patients reporting headache (P = 0.006), an 87.7% decrease in papilledema (P = 0.1), a 100% resolution of diplopia with VPS or LPS, and an 88.5% decrease in transient visual obscurations (P = 1). In the worse eye, improved visual acuity (VA) occurred in 53.7% of eyes (P = 1), was stable in 16.4%, and worsened in 29.8%. The mean LogMAR VA was improved by 0.06 LogMAR (20/68) in the worse eye (P = 0.97) and 0.08 LogMAR (20/31) in the better eye (P = 0.7). The visual function that impairs daily activity was decreased by 55.4% (P = 0.08). Patients shunted within 1 month of presentation had a significantly higher rate of headache (P = 0.04) and VA improvement (P < 0.001). CONCLUSIONS: VPS and LPS are effective in improving visual symptoms and headache in patients with IIH.

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.