LETTER TO THE EDITOR
SD-OCT in NIR modality to diagnose retinal microvascular abnormalities
in neurofibromatosis type 1
Received: 12 February 2018 / Revised: 22 May 2018 / Accepted: 29 May 2018
Springer-Verlag GmbH Germany, part of Springer Nature 2018
Neurofibromatosis type I (NF1), also known as Von
Recklinghausen’s disease, is one of the most common autoso-
mal dominant genetic disorders with an average prevalence of
1:4000 and an estimated incidence of 1:3000 .
The diagnosis of NF1 is based on the clinical criteria rec-
ommended by the NIH Consensus Conference which include
multiple café-au-lait spots (CLS), cutaneous or subcutaneous
neurofibromas, plexiform neuromas, axillary or inguinal
freckling, optic gliomas, distinctive osseous lesion, and iris
Lisch nodules .
Lisch nodules represent the most common ocular feature of
NF-1. Further ocular manifestations include optic gliomas, or-
bital and eyelid neurofibromas, eyelid café-au-lait spots, choroi-
dal nevi, congenital absence of the greater wing of the sphenoid
bone, congenital glaucoma, and choroidal abnormalities .
There are only a few reports in the literature that analyze
the presence of ocular abnormalities in NF-1 patients. The aim
of this study was to evaluate the prevalence of retinal abnor-
malities in a large sample of consecutive patients with NF1.
This study was conducted on 224 consecutive patients (123
females and 101 males, mean age 38.5 ± 20.5 years, range 5–
69 years) with NF1.
Each patient underwent a comprehensive ophthalmological
examination inclusive of best-corrected visual acuity, intraoc-
ular pressure measurement, slit-lamp biomicroscopy, indirect
fundus biomicroscopy, and spectral domain OCT
superimposed to near-infrared fundus images (NIR).
All patients underwent 1.5 Tesla MRI scan of the brain to
assess the presence of optic nerve gliomas.
Of the 224 patients, 84 patients (37.5%) had microvascular
abnormalities within 30° angle of the fovea on NIR. Retinal
vascular abnormalities were bilateral in 18 cases. Fifty-seven
(25.5%) patients had a single type of lesions; 22 patients
(12%) had two different types; and 5 patients (2.3%) presented
three different patterns of retinal microvascular abnormalities.
We identified three different vascular patterns based on
their appearance: (i) the simple tortuosity; (ii) the more com-
plex corkscrew; and iii) the moya moya-like configurations
(Fig. 1). In the Bcorkscrew^ pattern, we identified a spiral
attitude of vessels, while the moya moya-like configuration
was characterized by tortuous vessels that end in a Bpuff of
smoke^ arrangement that resembles the collateral circulation
seen in moya moya syndrome.
Of 224 patients, 57 subjects (25.5%) presented at least the
simple vascular tortuosity and 42 (18.7%) the corkscrew pat-
tern while 17 (7.5%) the moya moya-like type. These lesions
were predominantly unilateral and not associated with visual
Retinal microvascular abnormalities are not detectable at
indirect ophthalmoscopy exam due to their very small caliber,
while they can be easily identified with spectral domain OCT-
NIR fundus images. To our knowledge, there are only few
studies that have described these abnormalities in small series
of patients with NF1.In a study involving 32 patients with
NF1, retinal microvascular abnormalities were present in the
37.5% of the patients . Abdolrahimzadeh et al. found mi-
crovascular abnormalities in 35% of 17 patients .
Karadimas and Asensio-Sánchez reported corkscrew retinal
vessels in a single patient with NF1 [4, 5]. They were predom-
inantly unilateral, typically benign, and were not associated
with visual alteration. A recent paper of Parrozzani et al. re-
ported a prevalence of retinal vascular abnormalities in 6.1%
of patients with NF1 detected by infrared confocal scanning
laser ophthalmoscopy images . The Authors highlight that
* Marta Sacchetti
Department of Sense Organs, Sapienza University of Rome, Viale
del Policlinico 155, 00161 Rome, Italy
Department of Dermatology and Venereology, Sapienza University
of Rome, Policlinico Umberto I, Rome, Italy
Graefe's Archive for Clinical and Experimental Ophthalmology