Journal of Neuro-Ophthalmology, December 2003, Volume 23, Issue 4

Retinal Vascular Abnormalities in Neurofibromatosis Type 1

Microvascular retinal abnormalities, presenting in a corkscrew configuration, have been very recently described in patients with neurofibromatosis type 1 (NF-1). We report one more patient with NF-1 who had distinctive corkscrew retinal vessels superior and inferior to the fovea. This patient further supports the existence of a true association between this recently described retinal finding and NF-1.

PHOTO ESSAY Retinal Vascular Abnormalities in Neurofibromatosis Type 1 Panagiotis Karadimas, MD, Efterpi Hatzispasou, MD, and Evrydiki A. Bouzas, MD FIG. 1. Fundus, OS, shows microvascular abnormalities superior and inferior to the fovea. established by the National Institutes of Health ( 1). Best- corrected visual acuity was 20/ 20 bilaterally. An­terior segment examination revealed multiple Lisch nodules bilaterally. Retinal examination of the OD was unremarkable. Retinal examination of the OS revealed tortuous retinal venules in a corkscrew configuration superior to the fovea, adjacent to which a microvas­cular collateral- like network was noted. Inferior to the fovea, similar but less prominent tortuous venules were seen ( Figs. 1 and 2). No retinal edema was present clinically. The patient refused to undergo fluoresce­in angiography. NF- 1 is a common genetic disorder resulting in the formation of a variety of benign and malignant tumors ( 2). It has an autosomal dominant mode of inheritance with 100% penetrance and variable expressivity. The respon­sible gene has been located on the long arm of chromosome 17 and encodes for a protein termed " neurofibromin," which appears to be a tumor- suppression protein. Abstract: Microvascular retinal abnormalities, presenting in a corkscrew configuration, have been very recently de­scribed in patients with neurofibromatosis type 1 ( NF- 1). We report one more patient with NF- 1 who had distinctive corkscrew retinal vessels superior and inferior to the fovea. This patient further supports the existence of a true asso­ciation between this recently described retinal finding and NF- 1. ( JNeuro- Ophthalmol 2003; 23: 274- 275) A31- year- old Greek man was referred for a routine oph­thalmic examination. He had been diagnosed with neu­rofibromatosis type 1 ( NF- 1) according to the criteria From the 1 st Department of Ophthalmology, Henry Dunant Hospital, Athens, Greece. Address correspondence to Dr. Panagiotis Karadimas, Henry Dunant Hospital, 1st Department of Ophthalmology, 107 Mesogion Avenue, 11526 Athens, Greece; E- mail: t_ karadimas@ yahoo. com Copyright © Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited. 274 J Neuro- Ophthalmol, Vol. 23, No. 4, 2003 Retinal Vascular Abnormalities in NF- 1 JNeuro- Ophthalmol, Vol. 23, No. 4, 2003 FIG. 2. Red- free photograph shows tortuous retinal ve­nules in a corkscrew configuration superior ( arrows) and inferior ( small arrowheads) to the fovea. Adjacent to the superior corkscrew venules, a microvascular collateral- like network is present ( large arrowheads). Ms hamartomas, referred to as Lisch nodules, are the most common ocular finding in NF- 1. Other ophthalmic manifestations include plexiform neurofibromas of the eye­lids, orbital neurofibromas, orbital bone abnormalities, en­larged corneal nerves, congenital glaucoma, and optic path­way gliomas ( 2). Findings in the fundus include choroidal hamartomas ( present in one- third to one- half of adults with NF- 1), retinal astrocytic hamartomas, combined retinal and retinal pigment epithelial hamartomas, and retinal capillary hemangiomas ( 3). In 2002, Muci- Mendoza et al. ( 4) described a novel retinal finding in NF- 1, distinctive microvascular abnor­malities noted in 12 out of 32 ( 37.5%) patients. In 10 cases, the anomaly was very subtle, involving a second or third order venule, a tributary of the superior or inferior temporal veins, or, less frequently, the nasal veins. The tortuous ves­sel had a corkscrew appearance and ended in a minute tuft. In two of the patients, however, more striking abnormalities were observed: a venovenous anastomosis in the nasal retina and an extensive arteriovenous malformation coex­isting with an epiretinal membrane. Two of these 12 pa­tients also had choroidal neurofibromas. Fluorescein angi­ography obtained in half of the cases did not reveal any leakage. The condition did not disturb vision. According to the authors, this finding is a new retinal marker for NF- 1. References 1. National Institutes of Health Consensus Development Conference. Neurofibromatosis. Conference statement. Arch Neurol 1988; 45: 575- 8. 2. Sippel KC. Ocular findings in neurofibromatosis type 1. Int Oph­thalmol Clin. 2001; 41: 25- 40. 3. Destro M, D'Amico DJ, Gragoudas ES, et al. Retinal manifestations of neurofibromatosis. Diagnosis and management. Arch Ophthal­mol. 1991; 109: 662- 6. 4. Muci- Mendoza R, Ramella M, Fuenmayor- Rivera D. Corkscrew retinal vessels in neurofibromatosis type 1: report of 12 cases. Br J Ophthalmol. 2002; 86: 282- 4. Copyright © Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited. 275 [VBneurofibromatosisone]