Optical nerve contrast agent

Glaucoma is the leading cause of irreversible vision loss and comprises a group of chronic optic neuropathies characterized by progressive retinal ganglion cell (RGC) loss. Various etiologies, including impaired blood supply to the optic nerve, have been implicated for glaucoma pathogenesis. Optical coherence tomography angiography (OCTA) is a non-invasive imaging modality for visualizing the ophthalmic microvasculature. Using blood flow as an intrinsic contrast agent, it distinguishes blood vessels from the surrounding tissue...

PURPOSE: The purpose of this study was to investigate the clinical utility of three-dimension (3D) high-resolution inversion recovery (IR)-prepared fast spoiled gradient-recalled (SPGR) magnetic resonance imaging (MRI) in the diagnosis of cranial nerve meningeal carcinomatosis (MC). METHODS: A total of 114 patients with MC from January 2015 to March 2020 were enrolled and their MRIs were analyzed retrospectively. All patients underwent MRIs before being administered a contrast agent...

BACKGROUND: The glymphatic system actively exchanges cerebrospinal fluid (CSF) and interstitial fluid (ISF) to eliminate toxic interstitial waste solutes from the brain parenchyma. Impairment of the glymphatic system has been linked to several neurological conditions. Glioblastoma, also known as Glioblastoma multiforme (GBM) is a highly aggressive form of malignant brain cancer within the glioma category. However, the impact of GBM on the functioning of the glymphatic system has not been investigated...

Rats are a commonly used animal model for the study of the pathogenesis and novel treatments of glaucoma, which is induced experimentally using invasive, painful procedures. Peribulbar anaesthesia (PBA) is frequently used in people and domestic animals prior to ophthalmic surgeries to provide excellent perioperative analgesia. Our goal was to develop a PBA technique adapted to rat anatomy, improving the welfare of animals used as a model for glaucoma. Eighteen rat cadavers ( n  = 36 eyes) were used to establish the optimal needle insertion location...

Iatrogenic nerve injury represents one of the most feared surgical complications and remains a major morbidity across many surgical specialties. Currently, no clinically approved technique can directly enhance intraoperative nerve visualization, where intraoperative nerve identification continues to challenge even experienced surgeons. Fluorescence-guided surgery (FGS) has been successfully integrated into clinical medicine to improve safety and efficacy in the surgical arena. A number of tissue- and disease-specific contrast agents are in the clinical translation pipeline for future FGS integration...

The diagnostic power of the textural features and fractal dimension (FD) for early detecting diabetic retinopathy (DR) were quantitatively evaluated with optical coherence tomography angiography (OCTA). 41 normal healthy OD eyes (age: 46.41±13.69), and 10 diabetic OD eyes (age: 60.90±13.46) in the early stages of DR (mild or moderate non-proliferative diabetic retinopathy (NPDR)) were employed. Four retinal vascular plexuses including nerve fiber layer vascular plexus (NFLVP), superficial vascular plexus (SVP), intermediate capillary plexus (ICP) and deep capillary plexus (DCP) were generated by using OCTA...

BACKGROUND: Animal experiments have demonstrated the dependency of cerebrospinal fluid clearance function on age and sleep, which partially underlay the cognitive decline in the elderly. However, human evidence is lacking, which could be mainly attributed to the limited methods of cerebrospinal fluid clearance function assessment. METHOD: Serial T1-weighted and T2-fluid attenuated inversion recovery imaging were performed in 92 patients before and at multiple time points including 4...

RATIONALE: Kimura disease (KD) is a rare, chronic inflammatory disease characterized by painless subcutaneous nodules predominantly located in the head and neck regions. Orbital KD, which intrudes into the intraconal space and results in compressive optic neuropathy, is rare and has not been previously reported. PATIENT CONCERNS: A 68-year-old man presented with blurred vision and progressive proptosis in the left eye that had been present for 2 years. DIAGNOSIS: Magnetic resonance imaging of the brain revealed soft tissue lesions with contrast enhancement and restricted diffusion involving the bilateral eyelids, orbits, and intraconal region; those on the left side were more prominent than those on the right side...

BACKGROUND: Disease modifying treatments (DMTs) for multiple sclerosis include injectable drugs (iDMTs) like interferons (IFNs) or glatiramer acetate (GA), and newer agents (nDMTs) in oral and intravenous forms. nDMTs are usually applied in escalation and less frequently as initial treatment in pediatric-onset (POMS). OBJECTIVE: We intended to evaluate the effect of nDMTs in comparison with iDMTs by retrospective examination of our patients with POMS. METHOD: Clinical records of POMS cases who received nDMTs either as escalation or initial treatment and who had at least 12 months' follow-up in our clinic were examined in two groups: patients who were started on iDMTs and later switched to nDMTs (Group A), and those who received nDMTs from the beginning (Group B)...

Spider brain and central nervous system (CNS) have remained unexplored, due in part to the difficulty of observing these organs, usually only possible through histological preparations. Recently, internal anatomy studies have been supplemented by the inclusion of X- ray micro-CT. Unmineralized tissue such as the body of invertebrates requires a staining process to enhance tissue X-ray absorption and improve contrast during observation. Many current protocols are based on iodine staining requiring critical point drying (CPD) of the sample for optimal contrast...

OBJECTIVES: As described recently, intravenously injected gadolinium-based contrast agent (GBCA) penetrates into the anterior eye chamber (AC) and is drained from the retina to the distal optic nerve (ON) along perivascular spaces, which serves retinal homeostasis and was termed the orbital glymphatic system (GS). Independently, AC enhancement predicted ON infiltration, a major risk factor for advanced retinoblastoma (RB), in a small RB patient cohort. We aimed to review the supposed imaging biomarker for ON infiltration in a large RB cohort and with respect to the recently described orbital GS...

BACKGROUND: We describe a case of an atypical presentation of leukemic optic nerve infiltration. CASE PRESENTATION: A patient with acute lymphoblastic leukemia (ALL) in remission suffered from sudden right eye vision loss. At the time of presentation, the affected eye presented with an afferent pupillary defect, while the fundus examination was normal. A complete work up of the patient revealed no signs of ALL relapse, but MR imaging of the optic nerve showed contrast agent uptake consistent with optic nerve infiltration...

INTRODUCTION: Optic pathway gliomas are often asymptomatic tumors occurring in children with neurofibromatosis type 1 (NF1 + OPG) or sporadically (spOPG). Treatment is usually prompted by visual loss and/or tumor progression on MRI. The aim of this study was to investigate the relationship between visual acuity (VA), tumor growth, and contrast enhancement to provide more distinct indications for the administration of gadolinium-based contrast agents. METHODS: Tumor load was retrospectively measured and enhancement semi-quantitatively scored on 298 MRIs of 35 patients (63% NF1 + OPG)...

Disruption or loss of oligodendrocytes (OLs) and myelin has devastating effects on CNS function and integrity, which occur in diverse neurological disorders, including Multiple Sclerosis (MS), Alzheimer's disease and neuropsychiatric disorders. Hence, there is a need to develop new therapies that promote oligodendrocyte regeneration and myelin repair. A promising approach is drug repurposing, but most agents have potentially contrasting biological actions depending on the cellular context and their dose-dependent effects on intracellular pathways...

Purpose: Intraocular pressure (IOP) is currently the only modifiable risk factor for glaucoma, yet glaucoma can continue to progress despite controlled IOP. Thus, development of glaucoma neurotherapeutics remains an unmet need. Scutellarin is a flavonoid that can exert neuroprotective effects in the eye and brain. Here, we investigated the neurobehavioral effects of scutellarin treatment in a chronic IOP elevation model. Methods: Ten adult C57BL/6J mice were unilaterally injected with an optically clear hydrogel into the anterior chamber to obstruct aqueous outflow and induce chronic IOP elevation...

Pseudotumor cerebri, benign intracranial hypertension or idiopathic intracranial hypertension are all terms used for a neurological syndrome consisting of increased intracranial pressure, headache and possible edema of the optic nerve head and decreased visual function. Normal findings in contrast agent computed tomography or magnetic resonance imaging of the head in physiological neurological findings, with the exception of paresis VI, indicate an increase in pressure of laboratory normal cerebrospinal fluid (CSF) of unknown cause...

IMPORTANCE: Sentinel lymph node (SLN) mapping agents approved for current surgical practice lack sufficient brightness and target specificity for high-contrast, sensitive nodal visualization. OBJECTIVE: To evaluate whether an ultrasmall, molecularly targeted core-shell silica nanoparticle (Cornell prime dots) can safely and reliably identify optically avid SLNs in head and neck melanoma during fluorescence-guided biopsy. DESIGN, SETTING, AND PARTICIPANTS: This nonrandomized clinical trial enrolled patients aged 18 years or older with histologically confirmed melanoma in whom SLN mapping was indicated...

INTRODUCTION: Radiation-induced optic neuropathy (RION) is still a devastating complication of brain and skull base radiation that has no effective treatment up until today, thus uttermost caution must be taken in treating patients that brain radiotherapy is needed. We present two cases of RION that happened in seemingly safe radiation doses. CASE DESCRIPTION: A 48-year-old female with a history of pleomorphic pituitary adenoma developed bilateral and painless loss of vision 10 months after radiation to the brain; the total radiation dose was 45 Gy in 25 fractions and no other risk factors of RION were found...

INTRODUCTION: Transcranial color-coded duplex sonography (TCCS) with and without ultrasound contrast agent has been used to diagnose cerebral venous thrombosis, however, no experience in the diagnosis of patients with cerebral venous thrombosis and with dural arteriovenous fistula (dAVF) by contrast-enhanced TCCS has been reported yet. CASE REPORT: The authors reported a 49-year-old male patient with straight sinus (StS) thrombosis and dAVF. Plain TCCS and contrast-enhanced TCCS demonstrated the direct presentation of the selected feeder and drainage veins of the dAVFs, arterialized venous flow waveform, and an enlarged optic nerve sheath diameter, indicating an increased intracranial pressure, and a filling defect in the StS even after administration of an ultrasound contrast agent...

We aimed to assess the efficacy of biologic therapy in refractory non-Multiple Sclerosis (MS) Optic Neuritis (ON), a condition more infrequent, chronic and severe than MS ON. This was an open-label multicenter study of patients with non-MS ON refractory to systemic corticosteroids and at least one conventional immunosuppressive drug. The main outcomes were Best Corrected Visual Acuity (BCVA) and both Macular Thickness (MT) and Retinal Nerve Fiber Layer (RNFL) using Optical Coherence Tomography (OCT). These outcome variables were assessed at baseline, 1 week, and 1, 3, 6 and 12 months after biologic therapy initiation...