PURPOSE: Over the past two decades, advancements in imaging modalities have significantly evolved the diagnosis and management of retinal diseases. Through these novel platforms, we have developed a deeper understanding of the anatomy of the choroidal vasculature and the choriocapillaris. The recently developed tools such as optical coherence tomography (OCT) and OCT angiography (OCTA) have helped elucidate the pathological mechanisms of several posterior segment diseases. In this review, we have explained the anatomy of the choriocapillaris and its close relationship to the outer retina and retinal pigment epithelium. METHODS: A comprehensive search of medical literature was performed through the Medline/PubMed database using search terms: choriocapillaris, choroid, quantification, biomarkers, diabetic retinopathy, age-related macular degeneration, choroidal blood flow, mean blur rate, flow deficit, optical coherence tomography, optical coherence tomography angiography, fluorescein angiography, indocyanine green angiography, OCTA, Doppler imaging, uveitis, choroiditis, white dot syndrome, tubercular serpiginous-like choroiditis, choroidal granuloma, pachychoroid, toxoplasmosis, central serous chorioretinopathy, multifocal choroiditis, choroidal neovascularization, choroidal thickness, choroidal vascularity index, choroidal vascular density, and choroidal blood supply. The search terms were used either independently or combined with choriocapillaris/choroid. RESULTS: The imaging techniques which are used to qualitatively and quantitatively analyze choriocapillaris are described. The pathological alterations in the choriocapillaris in an array of conditions such as diabetes mellitus, age-related macular degeneration, pachychoroid spectrum of diseases, and inflammatory disorders have been comprehensively reviewed. The future directions in the study of choriocapillaris have also been discussed. CONCLUSION: The development of imaging tools such as OCT and OCTA has dramatically improved the assessment of choriocapillaris in health and disease. The choriocapillaris can be delineated from the stromal choroid using the OCT and quantified by manual or automated methods. However, these techniques have inherent limitations due to the lack of an anatomical distinction between the choriocapillaris and the stromal choroid, which can be overcome with the use of predefined segmentation slabs on OCT and OCTA. These segmentation slabs help in standardizing the choriocapillaris imaging and obtain repeatable measurements in various conditions such as diabetic retinopathy, age-related macular degeneration, pachychoroid spectrum, and ocular inflammations. Additionally, Doppler imaging has also been effectively used to evaluate the choroidal blood flow and quantifying the choriocapillaris and establishing its role in the pathogenesis of various retinochoroidal diseases. As tremendous technological advancements such as wide-field and ultra-wide field imaging take place, there will be a significant improvement in the ease and accuracy of quantifying the choriocapillaris.

PURPOSE: Pediatric optic neuritis (ON) is a rare disease that has not been well characterized. The Pediatric ON Prospective Outcomes Study (PON1) was the first prospective study to our knowledge aiming to evaluate visual acuity (VA) outcomes, including VA, recurrence risk, and final diagnosis 2 years after enrollment. DESIGN: Nonrandomized observational study at 23 pediatric ophthalmology or neuro-ophthalmology clinics in the United States and Canada. PARTICIPANTS: A total of 28 (64%) of 44 children initially enrolled in PON1 (age 3-<16 years) who completed their 2-year study visit. METHODS: Participants were treated at the investigator's discretion. MAIN OUTCOMES MEASURES: Age-normal monocular high-contrast VA (HCVA). Secondary outcomes included low-contrast VA (LCVA), neuroimaging findings, and final diagnoses. RESULTS: A total of 28 participants completed the 2-year outcome with a median enrollment age of 10.3 years (range, 5-15); 46% were female, and 68% had unilateral ON at presentation. Final 2-year diagnoses included isolated ON (n = 11, 39%), myelin oligodendrocyte glycoprotein-associated demyelination (n = 8, 29%), multiple sclerosis (MS) (n = 4,14%), neuromyelitis optica spectrum disease (NMOSD) (n = 3, 11%), and acute disseminated encephalomyelitis (n = 2, 7%). Two participants (7%; 95% confidence interval [CI], 1-24) had subsequent recurrent ON (plus 1 participant who did not complete the 2-year visit); all had MS. Two other participants (7%) had a new episode in their unaffected eye. Mean presenting HCVA was 0.81 logarithm of the minimum angle of resolution (logMAR) (∼20/125), improving to 0.14 logMAR (∼20/25-2) at 6 months, 0.12 logMAR (∼20/25-2) at 1 year, and 0.11 logMAR (20/25-1) at 2 years (95% CI, -0.08 to 0.3 [20/20+1-20/40-1]). Twenty-four participants (79%) had age-normal VA at 2 years (95% CI, 60-90); 21 participants (66%) had 20/20 vision or better. The 6 participants without age-normal VA had 2-year diagnoses of NMOSD (n = 2 participants, 3 eyes), MS (n = 2 participants, 2 eyes), and isolated ON (n = 2 participants, 3 eyes). Mean presenting LCVA was 1.45 logMAR (∼20/500-2), improving to 0.78 logMAR (∼20/125+2) at 6 months, 0.69 logMAR (∼20/100+1) at 1 year, and 0.68 logMAR (∼20/100+2) at 2 years (95% CI, 0.48-0.88 [20/50+1-20/150-1]). CONCLUSIONS: Despite poor VA at presentation, most children had marked improvement in VA by 6 months that was maintained over 2 years. Associated neurologic autoimmune diagnoses were common. Additional episodes of ON occurred in 5 (18%) of the participants (3 relapses and 2 new episodes).

Millions of people worldwide are bilaterally blind due to corneal diseases including infectious etiologies, trauma, and chemical injuries. While corneal transplantation can successfully restore sight in many, corneal graft survival decreases in eyes with chronic inflammation and corneal vascularization. Additionally, the availability of donor cornea material can be limited, especially in underdeveloped countries where corneal blindness may also be highly prevalent. Development of methods to create and implant an artificial cornea (keratoprosthesis) may be the only option for patients whose eye disease is not suitable for corneal transplantation or who live in regions where corneal transplantation is not possible. The Boston Keratoprosthesis (B-KPro) is the most commonly implanted keratoprosthesis worldwide, having restored vision in thousands of patients. This article describes the initial design of the B-KPro and the modifications that have been made over many years. Additionally, some of the complications of surgical implantation and long-term care challenges, particularly complicating inflammation and glaucoma, are discussed.

We describe in vivo follow-up PET imaging and postmortem findings from an autosomal dominant Alzheimer's disease (ADAD) PSEN1 E280A carrier who was also homozygous for the APOE3 Christchurch (APOE3ch) variant and was protected against Alzheimer's symptoms for almost three decades beyond the expected age of onset. We identified a distinct anatomical pattern of tau pathology with atypical accumulation in vivo and unusual postmortem regional distribution characterized by sparing in the frontal cortex and severe pathology in the occipital cortex. The frontal cortex and the hippocampus, less affected than the occipital cortex by tau pathology, contained Related Orphan Receptor B (RORB) positive neurons, homeostatic astrocytes and higher APOE expression. The occipital cortex, the only cortical region showing cerebral amyloid angiopathy (CAA), exhibited a distinctive chronic inflammatory microglial profile and lower APOE expression. Thus, the Christchurch variant may impact the distribution of tau pathology, modulate age at onset, severity, progression, and clinical presentation of ADAD, suggesting possible therapeutic strategies.

Objective: To investigate voxel-based morphometry (VBM) by using magnetic resonance imaging (MRI) in meibomian gland dysfunction patients with severe obesity (PATs) and to explore the application of VBM in the early diagnosis, prevention of cognitive impairment and targeted treatment of this disease. Methods: Sixteen PATs and 12 healthy controls (HCs) were enrolled and underwent MRI. Whole-head images were analyzed using VBM and data were compared between groups using an independent samples t-test. Receiver operating characteristic (ROC) curves were utilized to assess the diagnostic value of this approach. Mini-mental state examination (MMSE) scores were used to assess cognitive impairment and were analyzed using an independent samples t-test. Results: Compared with HCs, the VBM values in PATs were reduced in the left cerebellum and right thalamus but increased in the right brainstem, right precuneus and right paracentral lobule. The results of ROC curve analysis indicated that VBM may be useful in meibomian gland disease diagnosis. Comparison of MMSE scores between groups showed mild cognitive impairment in PATs. Conclusion: PATs showed altered VBM values in some brain areas. These findings may provide information about the pathophysiology of meibomian gland dysfunction and may help to explain the underlying mechanisms of clinical manifestations in PATs, such as cognitive impairment. Abnormal VBM values in these brain areas may serve as predictive factors for development of meibomian gland disease in severely obese people and as indicators for individualized treatment.