High axial myopia in neurofibromatosis type 1

Abstract

Background: Clinicians must be aware of phenotypic variability in neurofibromatosis type 1 (NF 1) presentations. There is perhaps a limited understanding on progression of NF 1 in prepubertal years and the subsequent threat to vision. Progressively increasing myopia may go unnoticed under a severely ptotic eyelid that gathers attention, due to a disfiguring mass in patients with NF 1. High myopia may result in recalcitrant amblyopia if not tackled early with multidisciplinary management. Clinical Description: A 12 year old girl had a history of progressively increasing left upper eyelid ptosis due to an upper eyelid mass, first noticed at the age of 1 year and eventually resulted in severe ptosis by the age of 5 years. However, this went unnoticed until she was diagnosed with NF 1 at the age of 12 years. Best corrected visual acuity was 6/6 (Plano) in the right eye (OD) and counting finger 2 m with − 15.0 diopter spheres in the left eye (OS). Peripheral fundus examination was normal in both eyes. Levo elevation and abduction were limited OS. Hypotropia, pulsatile proptosis, and depression of the globe were clinically attributable to enlargement of orbital tissues and lid problems. Contrast enhanced computed tomography scan revealed plexiform NF with extraconal extensions. Axial length was 21.94 mm OD and 28.92 mm OS. B scan ultrasound revealed a posterior staphyloma OS. Management: The patient underwent a debulking surgery of the eyelid mass which on histopathological examination confirmed plexiform NF. Surgery resulted in a cosmetic reduction in ptosis; however, any intervention was relatively too late to rehabilitate the left eye. Conclusions: Eye care certainly has its regional differences. High axial myopia may result in low VA and recalcitrant amblyopia that may go unrecognized and comes with management challenges to the attending ophthalmologist and allied specialties dealing with these cases of NF 1.