Neurofibromatosis type 1 (NF 1) is a multisystemic genetic disorder involving aberrant proliferation of multiple tissues of a neural crest origin. It represents a tumor predisposition syndrome characterized by a wide range of clinical manifestations, such as benign tumors, which primarily affect the skin and the nervous system. The most frequent clinical signs of NF 1 include café-au-lait spots all over the surface of the skin and axillary freckling; however, these signs can be accompanied by more severe manifestations such as the growth of both benign and malignant nervous system tumors and skeletal dysplasia, as well as a wide range of ocular manifestations. We report the rare case of retinal microvascular alterations and choroidal nodules in a 15 year old male patient with NF 1, detectable on optical coherence tomography angiography (OCTA). The hyperreflective choroidal nodules modified the profile of the choroidal vasculature. The retinal microvascular alterations in the form of clustered capillaries were detected in the superficial capillary plexus located nasally to the macular region. Retinal vascular abnormalities undetectable on fundus photography or fundoscopy can be present in patients with NF 1. Indirect ophthalmoscopy of our study patient was unremarkable. However, retinal vascular abnormalities were seen on OCTA scans in the superficial capillary plexus and choroidal nodules were detected on raster OCT scans. OCTA represents a useful imaging technique for detecting retinal microvascular abnormalities, which can be considered additional distinctive signs of NF 1.

UNASSIGNED: To examine whether image processing of non-mydriatic DRI Triton SS-OCT (Topcon Corporation, Tokyo, Japan) using the red free filter could assess the presence of choroidal nodules and thus include their detection as a diagnostic criterion in neurofibromatosis type 1 (NF1).
UNASSIGNED: We included 417 eyes from 210 patients, 377 - from 190 patients diagnosed with NF1 according to the criteria established by the National Institutes of Health Consensus Development Conference (NIH) and 40 from 20 healthy patients as a control group. The mean age was 9.4 years (range 2 years-18 years). All patients had their visual acuity measured by a test according to age, were examined for the presence of lisch nodules and an Optical Coherence Tomography (OCT) of the macular area was performed. All the OCT images were analysed to check if visible nodules could be identified.
UNASSIGNED: Ages 14 (95% CI=(9.7,18.3)) and 12 years (95% CI=(9.1,14)) are the cut-off points that best separate those with choroidal nodules with Triton OCT and lisch with slit lamp, respectively, from those without. lisch nodules were detected in 50% of cases of NF1 patients. The presence of choroidal nodules did not present a statistically significant correlation with the occurrence of optic pathway glioma (p = 0.96) nor with the patient\'s visual worsening (p = 0.072). A statistically significant correlation was observed between the presence of choroidal nodules and the presence of lisch nodules (p < 0.05).
UNASSIGNED: The Topcon Triton OCT red free tool would not be a good tool to detect choroidal nodules in patients with NF1 because of its low sensitivity. If the presence of choroidal nodules were to be included in the diagnostic criteria for NF1, it would be convenient to use a device with red and infrared radiations.

UNASSIGNED: To describe optical coherence tomography angiography (OCTA) findings in the retina and choroid of patients with neurofibromatosis type 1 (NF1).
UNASSIGNED: We describe a series of four patients diagnosed with NF1 and choroidal nodules who underwent a comprehensive ophthalmic evaluation including a retinal multimodal imaging study based on retinography, near-infrared reflectance imaging (NIR), enhanced depth imaging (EDI) optical coherence tomography (OCT) and OCTA.
UNASSIGNED: Patients were three women and one man aged 36-47 years. In all patients, the choroidal nodules were not visible in retinographies but easily detectable with NIR, appearing as multiple bright patches. On OCTA, we observed reduced vessel density in the choriocapillaris in zones where choroidal nodules appeared in OCT images. In one patient, a corkscrew vessel was visible in the superficial capillary plexus.
UNASSIGNED: Choriocapillaris vessel density was reduced in zones where choroidal nodules occur in NF1 patients. Further work is needed to clarify the clinical relevance of this finding.

Neurofibromatosis Type I (NF1), also termed von Recklinghausen disease, is a rare genetic disorder that is transmitted by autosomal dominant inheritance, with complete penetrance and variable expressivity. It is caused by mutation in the NF1 gene on chromosome 17 encoding for neurofibromin, a protein with oncosuppressive activity, and it is 50% sporadic or inherited. The disease is characterized by a broad spectrum of clinical manifestations, mainly involving the nervous system, the eye and skin, and a predisposition to develop multiple benign and malignant neoplasms. Ocular diagnostic hallmarks of NF1 include optic gliomas, iris Lisch nodules, orbital and eyelid neurofibromas, eyelid café-au-lait spots. Choroidal nodules and microvascular abnormalities have recently been identified as additional NF1-related ocular manifestations. The present study was designed to describe the features and clinical significance of a new sign related to the visual apparatus in NF-1, represented by hyperpigmented spots (HSs) of the fundus oculi.
HSs were detected in 60 (24.1%) out of 249 patients with NF1, with a positive predictive value of 100% and a negative predictive value of 44.2%. None of the healthy subjects (150 subjects) showed the presence of HSs. HSs were visible under indirect ophthalmoscopy, ultra-wide field (UWF) pseudocolor imaging and red-only laser image, near-infrared reflectance (NIR)-OCT, but they were not appreciable on UWF green reflectance. The location and features of pigmentary lesions matched with the already studied NF1-related choroidal nodules. No significant difference was found between the group of patients (n = 60) with ocular HSs and the group of patients (n = 189) without ocular pigmented spots in terms of age, gender or severity grading of the disease. A statistically significant association was demonstrated between the presence of HSs and neurofibromas (p = 0.047), and between the presence of HSs and NF1-related retinal microvascular abnormalities (p = 0.017).
We described a new ocular sign represented by HSs of the fundus in NF1. The presence of HSs was not a negative prognostic factor of the disease. Following multimodal imaging, we demonstrated that HSs and choroidal nodules were consistent with the same type of lesion, and simple indirect ophthalmoscopy allowed for screening of HSs in NF1.

Neurofibromatosis type 1 is an autosomal dominant neurocutaneous disorder affecting 1 in 3000 births. This familial tumor predisposition syndrome is diagnosed clinically and affects the skin, bones, and nervous system. Malignant tumors can arise in childhood or adulthood and are the most common cause of mortality in this population. Early diagnosis and management led by a multidisciplinary team remains the standard of care, particularly in the management of optic pathway glioma. Emerging concepts in the genetic patterns of this condition have led to the introduction of new treatment modalities that target the mitogen-activated protein kinase and the mammalian target of rapamycin pathways. In this review, the role of the ophthalmologist and approach to screening for optic pathway glioma are outlined based on previous recommendations. Updates on choroidal involvement, as a diagnostic criterion, will also be discussed, further highlighting the pivotal role of the ophthalmologist in the diagnosis and management of this complex condition.

OBJECTIVE: To report 3 cases of neurofibromatosis type 1 (NF1) with choroidal nodules associated with retinal microvascular changes imaged with optical coherence tomography angiography (OCTA).
METHODS: Small case series in 3 NF1 patients. OCTA examinations were performed by a trained examiner (J.J.) after pupillary dilation. A standard scan, centered over the macula measuring 6 × 6 mm and 3 × 3 mm was obtained according to the findings on standard color photography. Additional scans were obtained in the zones with microvascular abnormalities. The segmentation provided by the machine software was used.
RESULTS: Corkscrew retinal vessels were observed in association with \"placoid\"-type choroidal nodules as shown by near-infrared reflectance imaging. In all cases, multiple lesions were found. They were second- or third-order tortuous vessels originating from the superior or inferior temporal veins. OCTA demonstrated that the tortuous venules were located in the superficial capillary plexus, and no abnormalities were found in the deep capillary plexus.
CONCLUSIONS: Corkscrew retinal vessels are part of a spectrum of retinal microvascular alterations seen in association, sometimes overlying choroidal nodules in patients with NF1 and are visualized in the superficial capillary plexus on OCTA. We demonstrated with OCTA that they are not associated with flow loss or ischemia in the superficial and deep capillary plexus. The link between the underlying nodule remains unclear. Since neovascularization was described in choroidal ganglioneuroma, we hypothesize that corresponding secretory substances from Schwann cells, ganglion cells, or melanocytes in choroidal nodules might alter the retinal vasculature.
CONCLUSIONS: We report on 3 cases of NF1 with choroidal nodules in association with retinal microvascular changes imaged with OCTA. OCTA demonstrated preservation of the blood flow in the deep and superficial capillary plexus of the retina. We hypothesize that angiogenic factors secreted by the underlying choroidal nodules could have an effect on the retinal vasculature. Further immunohistological studies in NF1 patients with choroidal nodules to detect angiogenic factors (such as VEGF) are necessary to confirm this hypothesis.