Orbital manifestations of Noonan syndrome.

: Noonan syndrome describes a rare multisystem condition that manifests with Turner syndrome phenotype combined with numerous systemic and facial characteristics. The most common systemic findings include cardiac defects, short stature, chest deformity, hearing loss, and bleeding diatheses. Patients with Noonan syndrome are also at a greater risk of developing various types of malignancies. Facial characteristics of Noonan syndrome consist of broad forehead, low-set ears, short and webbed neck, and low hairline. External ocular findings include hypertelorism, ptosis, epicanthal folds, antimongoloid slant, downward-sloping palpebral fissures, and malar flattening. In this case series and review of the literature, the authors present 2 cases of Noonan syndrome that embody the diverse spectrum of orbital manifestations associated with this rare disorder. The first case demonstrates more profound orbital pathology, including bilateral orbital giant cell reparative granulomas, proptosis, hypertelorism, shallow orbits, upper eyelid ptosis, and lower eyelid retraction. The second case displays classic Turner-syndrome-like facial characteristics including a broad forehead with low hairline, low-set ears, and short and webbed neck. Orbital findings were subtle and consisted of bilateral lower eyelid retraction and shallow orbits. In conclusion, Noonan syndrome is a rare congenital disorder with a wide spectrum of clinical findings. Various intraorbital and extraorbital tumors may occur in patients with Noonan syndrome, with giant cell reparative granuloma being the most commonly encountered. In patients with orbital tumors and eyelid retraction, the authors describe successful treatment through decompression, tumor extraction, and lower eyelid retractor release. Patients who present with ocular irritation and exposure due to less severe lower eyelid malposition may be successfully treated with lower eyelid retraction repair combined with lateral internal tarsoconjunctival tarsorrhaphy.