Increased 18F-FDG Uptake in the Posterior Ocular Bulb Is Associated with Brain Metastasis: A Retrospective Study
- Resource Type
- Authors
- Nghi Nguyen; E. Isin Akduman; Medhat Osman; Mohamed Sayed; Dana Oliver
- Source
- American Journal of Roentgenology. 191:W268-W274
- Subject
- Male
Pathology
medicine.medical_specialty
Lung Neoplasms
genetic structures
Visual interpretation
Sensitivity and Specificity
18f fdg uptake
Fluorodeoxyglucose F18
medicine
Humans
Tissue Distribution
Radiology, Nuclear Medicine and imaging
Lung
medicine.diagnostic_test
Brain Neoplasms
business.industry
Eye Neoplasms
Fdg uptake
Reproducibility of Results
Retrospective cohort study
General Medicine
Middle Aged
medicine.disease
eye diseases
Bulb
medicine.anatomical_structure
Positron emission tomography
Positron-Emission Tomography
Female
Radiopharmaceuticals
Nuclear medicine
business
Brain metastasis
- Language
- ISSN
- 1546-3141
0361-803X
An observation of increased (18)F-FDG uptake in the posterior ocular bulb led us to the hypothesis that increased posterior ocular bulb uptake is likely abnormal and may indicate intracranial lesions.Fifteen healthy volunteers and 35 patients with lung carcinoma-14 without brain metastasis and 21 with brain metastases-were retrospectively studied. The individuals underwent whole-body PET/CT including the brain with low-dose and unenhanced CT. Two nuclear medicine physicians visually analyzed the posterior ocular bulb uptake of both eyes. Standardized uptake values (SUVs) in the posterior ocular bulb were compared among the study groups. A radiologist reviewed brain MRI scans for abnormalities in the ocular bulbs and orbits.Visual interpretation showed normal FDG uptake at the posterior ocular bulb in 14 of the 15 healthy volunteers and 12 of the 14 (86%) patients without brain metastasis. Seventeen of the 21 (81%) patients with brain metastases showed increased uptake in the posterior ocular bulb. Visual interpretation showed no statistically significant difference between the healthy volunteers and patients without brain metastasis (p = 0.671). However, there was a significant difference between the patients with brain metastases and healthy volunteers as well as patients without brain metastasis (both, p0.001). High interrater agreement (kappa = 0.83) was noted. Brain MRI showed no abnormalities at the posterior ocular bulb in all study subjects. SUV results were inaccurate because of the intense tracer activity in the posterior orbit nearby. A good correlation between visually increased posterior ocular bulb uptake and the presence of brain metastasis was present (Cramer's V = 0.61).Visually increased FDG uptake along the posterior ocular bulb is an abnormal finding and may indicate intracranial structural abnormalities such as brain metastases.