Abstract
Purpose: :
To elicit the utility of PET imaging in identifying systemic inflammation that may lead to the diagnosis and treatment of patients with active uveitis.
Methods: :
Retrospective, interventional case series of patients presenting to the Uveitis Service at the Walter Reed Army Medical Center between 2007 and 2010. Patients with uveitis of unknown etiology were evaluated with a preliminary lab screening including ACE, HLA-B27, Lyme Antibody, ANA, RPR, and FTA blood work. They also had screening chest radiographs or chest CT. They were then evaluated with PET imaging. Guided by clinical course or PET imaging, interventional biopsy of lymph nodes or vitrectomy was performed for tissue diagnosis.
Results: :
Thirteen patients were evaluated with active uveitis. Five of the twelve patients (41.7%) had positive PET imaging. Four of the five patients with positive PET scans were diagnosed with sarcoidosis. A frontal lobe mass was identified in the other patient with a positive PET scan. This patient was later diagnosed with primary CNS lymphoma. In two of the patients with positive PET findings, the hypermetabolic foci were in locations that could be biopsied. These two patients had a tissue diagnosis of sarcoidosis. Four of the twelve patients (33.3%) had non-conclusive lab work and negative imaging. These patients were diagnosed with presumed ocular sarcoidosis based on clinical findings. Three of the twelve patients (25%) remain without an identified etiology for their inflammation.
Conclusions: :
PET imaging proved useful, aiding in the diagnosis of five of the twelve patients (41.7%). Due to its cost and time intensive nature, PET imaging may be most beneficial in patients with unusual presentations of uveitis. This includes patients with recurrent or recalcitrant uveitis or when preliminary lab and radiologic studies do not lead to a definitive diagnosis.
Keywords: imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound)