Homonymous Retinal Ganglion Cell Layer Atrophy With Asymptomatic Optic Tract Glioma in Neurofibromatosis Type I

Neurofibromatosis Type 1: Optimizing Management with a Multidisciplinary Approach

Neurofibromatosis Type I (NF1) is a complex genetic condition that affects multiple organ systems and presents a unique set of challenges for clinicians in its management. NF1 is a tumor predisposition syndrome that primarily affect the peripheral and central nervous systems via the impact of haploinsufficiency upon neural crest lineage cells including Schwann cells, melanocytes, fibroblasts, etc. NF1 can further lead to pathology of the skin, bones, visual system, and cardiovascular system, all of which can drastically reduce a patient's quality of life (QOL). This review provides a comprehensive examination of the many specialties required for the care of patients with Neurofibromatosis Type 1 (NF1). We delve into the pathogenesis and clinical presentation of NF1, highlighting its diverse manifestations and the challenges they pose in management. The review underscores the importance of a multidisciplinary approach to NF1, emphasizing how such an approach can significantly improve patient outcomes and overall QOL. Central to this approach is the role of the NF expert, who guides a multidisciplinary team (MDT) comprising healthcare professionals from many areas of expertise. The MDT collaboratively addresses the multifaceted needs of NF1 patients, ensuring comprehensive and personalized care. This review highlights the need for further investigation to optimize the workflow for NF1 patients in an MDT setting, and to improve implementation and efficacy.

Recent advances in the use of optical coherence tomography in neuro-ophthalmology: A review

Optical coherence tomography (OCT) is an in vivo imaging modality that provides non-invasive, high resolution and fast cross-sectional images of the optic nerve head, retina and choroid. OCT angiography (OCTA) is an emerging tool. It is a non-invasive, dye-free imaging approach of visualising the microvasculature of the retina and choroid by employing motion contrast imaging for blood flow detection and is gradually receiving attention for its potential roles in various neuro-ophthalmic and retinal conditions. We will review the clinical utility of the OCT in the management of various common neuro-ophthalmic and neurological disorders. We also review some of the OCTA research findings in these conditions. Finally, we will discuss the limitations of OCT as well as introduce other emerging technologies.

Monocular Visual Field Defect on Humphrey 24-2 SITA-Fast Testing Later Identified as a Highly Incongruous Homonymous Defect on Humphrey 30-2 SITA-Fast Testing

Monocular visual field defects generally localize at or anterior to the optic chiasm, while homonymous hemianopias localize to the retrochiasmal visual pathway. Highly incongruous visual field defects may be difficult to identify on 24-2 Humphrey visual field testing, and this case demonstrates the value of optical coherence tomography (OCT) ganglion cell-inner plexiform layer (GCIPL) in rapidly localizing the lesion. A 54-year-old woman was found on routine examination to have an isolated superonasal quadrant visual field defect respecting the vertical meridian in the left eye only on Humphrey 24-2 SITA-Fast testing. She had a remote history of significant head trauma. Visual acuity, anterior segment, and fundus examination were normal. OCT revealed a bow-tie atrophy of the retinal nerve fiber layer in the right eye (OD), and binocular homonymous hemi-macular atrophy of OCT GCIPL, confirming the localization was the left retrochiasmal visual pathway. A repeat Humphrey 30-2 SITA-Fast visual field demonstrated that the visual field defect was also present in the OD in a highly incongruous manner. Magnetic resonance imaging of the brain with contrast showed mild atrophy of the left optic tract. This case demonstrates that highly incongruous visual field defects may be difficult to identify on Humphrey 24-2 SITA-Fast visual fields, and OCT GCIPL serves as a rapid way to localize the lesion. More detailed visual field testing including 30-2 programs should be considered in these cases.

Recent advances and future directions on the use of optical coherence tomography in neuro-ophthalmology

Optical coherence tomography (OCT) is a noninvasive imaging technique used to qualitatively and quantitatively analyze various layers of the retina. OCT of the retinal nerve fiber layer (RNFL) and ganglion cell-inner plexiform layer (GCIPL) is particularly useful in neuro-ophthalmology for the evaluation of patients with optic neuropathies and retrochiasmal visual pathway disorders. OCT allows for an objective quantification of edema and atrophy of the RNFL and GCIPL, which may be evident before obvious clinical signs and visual dysfunction develop. Enhanced depth imaging OCT allows for visualization of deep structures of the optic nerve and has emerged as the gold standard for the detection of optic disc drusen. In the evaluation of compressive optic neuropathies, OCT RNFL and GCIPL thicknesses have been established as the most important visual prognostic factor. There is increasing evidence that inclusion of OCT as part of the diagnostic criteria for multiple sclerosis (MS) increases its sensitivity. Moreover, OCT of the RNFL and GCIPL may be helpful in the early detection and monitoring the treatment of conditions such as MS and Alzheimer's disease. OCT is an important aspect of the neuro-ophthalmologic assessment and its use is likely to increase moving forward.