PT - JOURNAL ARTICLE AU - Annemarie Klingenstein AU - Gerd-Ullrich Mueller-Lisse AU - Alexander R Haug AU - Aylin Garip-Kuebler AU - Christina V Miller AU - Christoph R Hintschich TI - Combined positron emission tomography/computed tomography (PET/CT) for imaging of orbital tumours and tumours extending into the orbit AID - 10.1136/bjophthalmol-2015-307988 DP - 2016 Oct 01 TA - British Journal of Ophthalmology PG - 1403--1408 VI - 100 IP - 10 4099 - http://bjo.bmj.com/content/100/10/1403.short 4100 - http://bjo.bmj.com/content/100/10/1403.full SO - Br J Ophthalmol2016 Oct 01; 100 AB - Objective To assess clinical and radiological performance of combined positron emission tomography/computed tomography (PET/CT) in patients with secondary and primary intraorbital tumours.Methods 14 adults with secondary and 1 child with primary orbital masses underwent combined whole-body PET/CT. Radiopharmaceutical tracers applied were (18F)-fluorodeoxyglucose, (18F)-fluoroethylcholine (FEC) and (68Ga)-DOTATATE. Histopathology and/or all conventional radiographic work-up and clinical course served as standard of reference. Descriptive statistics and Fisher's exact test were used for analysis.Results PET/CT detected all orbital masses. All 15 patients had malignant disease. Local osseous infiltration was correctly identified in 11 patients. Lymph node metastases were present in two of eight patients (25%) with haematogenous orbital metastases and in five of six patients (83%) with infiltrative carcinoma (p=0.05). Further distant metastases were present in all eight patients suffering from orbital metastases, but only one patient with infiltrative carcinoma (17%) presented with disseminated disease (p=0.003). In one metastasis, PET/CT excluded vital orbital tumour tissue after radiation therapy. Local recurrence was detected in another patient suffering from prostate cancer.Conclusion PET/CT is a sensitive tool for the detection and localisation of orbital masses, enabling assessment of both morphology and cell metabolism. Detailed imaging of the head and neck region with a small field-of-view should be performed when suspecting lymphatic metastases. As metastatic disease to the orbit is associated with advanced disease, focus should be laid on whole-body imaging for staging of these patients. Different radiopharmaceutical tracers can be applied to distinguish the origin of orbital metastases.