Optical coherence tomography angiography of choroidal nodules in neurofibromatosis type-1: A case series

Neurofibromatosis Type 1-Retinal Alterations Detectable with Optical Coherence Tomography Angiography

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.

Choroidal Hyperreflective Nodules Detected by Infrared Reflectance Images Are a Diagnostic Criterion for Neurofibromatosis Type 1 Patients Excluding Those with High Myopia

Neurofibromatosis type 1 (NF1) is one of the central nervous system’s most common autosomal dominant conditions. The diagnosis is based on the clinical diagnostic criteria and/or a molecularly confirmed mutation in the NF1 gene. This study investigated the possibility of substantiating choroidal nodules as a diagnostic criterion for the disease, including patients affected with and without high myopia. A cross-sectional study was carried out in 60 eyes of 30 adult patients diagnosed with NF1. A total of 30 healthy individuals of equivalent age and sex served as control. The Spectralis HRA+OCT MultiColor (Heidelberg Engineering GmbH, Heidelberg, Germany) evaluated the presence of choroidal abnormalities with near-infrared reflectance imaging. Secondly, the presence of iridian Lisch nodules was evaluated by slit lamp examination. Near-infrared reflectance imaging showed the presence of choroidal hyperreflective nodules in 83% of the patients diagnosed with NF1, while these choroidal abnormalities were not observed in any control subject. The patients diagnosed with NF1 associated with high myopia were the only ones who did not present the characteristic choroidal disorders. Therefore, when excluding patients diagnosed with high myopia, choroidal nodules were more frequent than Lisch nodules in a statistically significant proportion. Hyperreflective nodules detected by near-infrared reflectance imaging are as regular as Lisch nodules or even significantly more frequent when excluding high myope patients. Our observation of the mutual exclusion of choroidal hyperreflective nodules and high myopia in the NF1 patients seems a novel and interesting remark.

Intervortex Venous Anastomosis in the Macula in Central Serous Chorioretinopathy Imaged by En Face Optical Coherence Tomography

PURPOSE

To assess the presence of macular intervortex venous anastomosis in central serous chorioretinopathy (CSCR) patients using en face optical coherence tomography (EF-OCT).

METHODS

A cross-sectional study where EF-OCT 6 × 6 and 12 × 12 mm macular scans of patients with unilateral chronic CSCR were evaluated for anastomosis between vortex vein systems in the central macula. The presence of prominent anastomoses was defined as a connection with a diameter ≥150 µm between the inferotemporal and superotemporal vortex vein systems which crossed the temporal raphe. Three groups were studied: CSCR eyes (with an active disease with the presence of neurosensorial detachment; n = 135), fellow unaffected eyes (n = 135), and healthy eyes as controls (n = 110). Asymmetries, abrupt termination, sausaging, bulbosities and corkscrew appearance were also assessed.

RESULTS

In 79.2% of the CSCR eyes there were prominent anastomoses in the central macula between the inferotemporal and superotemporal vortex vein systems, being more frequent than in fellow eyes and controls (51.8% and 58.2% respectively). The number of anastomotic connections was higher in the affected eye group (2.9 ± 1.8) than in the unaffected fellow eye group (2.1 ± 1.7) and the controls (1.5 ± 1.6) (p < 0.001). Asymmetry, abrupt terminations and the corkscrew appearance of the choroidal vessels were more frequent in the affected eyes, although no differences in sausaging or bulbosities were observed.

CONCLUSIONS

Intervortex venous anastomoses in the macula were common in CSCR, being more frequently observed in affected eyes than in fellow unaffected eyes and healthy controls. This anatomical variation could have important implications concerning the pathogenesis and classification of the disease.

An update on choroidal abnormalities and retinal microvascular changes in neurofibromatosis type 1

Neurofibromatosis Type 1 (NF1) is a rare neurocutaneous disorder transmitted in an autosomal dominant fashion, mainly affecting the nervous system, the eye and skin. Ocular diagnostic hallmarks of NF1 include iris Lisch nodules, optic gliomas, orbital and eyelid neurofibromas, eyelid café-au-lait spots. In recent years, a new ocular sign represented by choroidal abnormalities (CAs) has been characterized in NF1. The CAs, identified with near-infrared reflectance, have been reported with a frequency of up to 100% in NF1, and have recently been added to the actual diagnostic criteria for NF1. The present Letter to the journal is intended to provide an update on features and clinical significance of CAs in NF1. Moreover, the relation with other ocular manifestations recently described in NF1 including hyperpigmented spots and retinal microvascular abnormalities is discussed.