Stephanie Ming Young1, Yoon-Duck Kim2, Gang Seok Jeon3, Kyung In Woo4. 1. Department of Ophthalmology, National University Hospital, Singapore; Department of Ophthalmology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea. 2. Department of Ophthalmology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea. Electronic address: ydkimoph@skku.edu. 3. Samsung Bright Eye Clinic, Gyeonggi-do, South Korea. 4. Department of Ophthalmology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea.
Abstract
PURPOSE: To review the radiological findings of frontal nerve schwannoma of the orbit and determine distinguishing imaging features. DESIGN: Retrospective interventional case series. METHODS: Setting: Single tertiary institution. PERIOD: September 1996 to December 2016. PATIENT POPULATION: Thirteen patients with orbital frontal nerve schwannoma. INTERVENTION: Patients underwent surgical excision following preoperative imaging. MAIN OUTCOME MEASURES: Imaging characteristics on computed tomography (CT) and magnetic resonance imaging (MRI). RESULTS: There were 13 patients with histopathologically proven schwannoma of the frontal nerve. Mean age was 44.4 years and 61.5% were male. The majority (84.6%) of frontal nerve schwannomas extended between the supraorbital notch and superior orbital fissure. The most common shape seen in our patients with frontal nerve schwannoma was a multilobulated "beaded" appearance (46.2%), followed by a dumbbell (30.8%), oval (15.4%), and fusiform (7.7%) shape. On CT imaging, all patients had bony remodeling. Target sign, fascicular sign, and cystic degeneration were seen in 76.9%, 35.8%, and 46.2% of patients, respectively. On radiological-pathologic correlation, the zone of tightly packed cellular solid portion (Antoni A pattern) corresponded to the hypointense area on T2-weighted MRI and the hyperintense area on gadolinium-enhanced T1-weighted MRI. CONCLUSION: Frontal nerve schwannoma should be considered as a differential diagnosis for any superior orbital mass. Our study describes several radiological findings that would point toward its diagnosis, including its multilobulated beaded or dumbbell shape, as well as additional signs such as the target sign, fascicular sign, and cystic degeneration.
PURPOSE: To review the radiological findings of frontal nerve schwannoma of the orbit and determine distinguishing imaging features. DESIGN: Retrospective interventional case series. METHODS: Setting: Single tertiary institution. PERIOD: September 1996 to December 2016. PATIENT POPULATION: Thirteen patients with orbital frontal nerve schwannoma. INTERVENTION: Patients underwent surgical excision following preoperative imaging. MAIN OUTCOME MEASURES: Imaging characteristics on computed tomography (CT) and magnetic resonance imaging (MRI). RESULTS: There were 13 patients with histopathologically proven schwannoma of the frontal nerve. Mean age was 44.4 years and 61.5% were male. The majority (84.6%) of frontal nerve schwannomas extended between the supraorbital notch and superior orbital fissure. The most common shape seen in our patients with frontal nerve schwannoma was a multilobulated "beaded" appearance (46.2%), followed by a dumbbell (30.8%), oval (15.4%), and fusiform (7.7%) shape. On CT imaging, all patients had bony remodeling. Target sign, fascicular sign, and cystic degeneration were seen in 76.9%, 35.8%, and 46.2% of patients, respectively. On radiological-pathologic correlation, the zone of tightly packed cellular solid portion (Antoni A pattern) corresponded to the hypointense area on T2-weighted MRI and the hyperintense area on gadolinium-enhanced T1-weighted MRI. CONCLUSION:Frontal nerve schwannoma should be considered as a differential diagnosis for any superior orbital mass. Our study describes several radiological findings that would point toward its diagnosis, including its multilobulated beaded or dumbbell shape, as well as additional signs such as the target sign, fascicular sign, and cystic degeneration.
Authors: Gary John V Mercado; Leandro Victor L Arcena; Elaine Yatco-Omańa; Elizabeth Y Arcellana-Nuqui; Roland Joseph D Tan Journal: Int J Ophthalmol Date: 2022-09-18 Impact factor: 1.645